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Sunday, November 16, 2014

Multiverse-canal connection

Here's a place where old canal history intersects with cutting-edge physics. From an article at Quanta: "Multiverse Collisions May Dot the Sky," by Jennifer Ouellette*:
In August 1834, a Scottish engineer named John Scott Russell was conducting experiments along Union Canal with an eye toward improving the efficiency of the canal boats. One boat being drawn by a team of horses stopped suddenly, and Russell noted a solitary wave in the water that kept rolling forward at a constant speed without losing its shape. The behavior was unlike typical waves, which tend to flatten out or rise to a peak and topple quickly. Intrigued, Russell tracked the wave on horseback for a couple of miles before it finally dissipated in the channel waters. This was the first recorded observation of a soliton. 
Russell was so intrigued by the indomitable wave that he built a 30-foot wave tank in his garden to further study the phenomenon, noting key characteristics of what he called “the wave of translation.” Such a wave could maintain size, shape and speed over longer distances than usual. The speed depended on the wave’s size, and the width depended on the depth of the water. And if a large solitary wave overtook a smaller one, the larger, faster wave would just pass right through. 
Russell’s observations were largely dismissed by his peers because his findings seemed to contradict what was known about water wave physics at the time. It wasn’t until the mid-1960s that such waves were dubbed solitons and physicists realized their usefulness in modeling problems in diverse areas such as fiber optics, biological proteins and DNA. Solitons also turn up in certain configurations of quantum field theory. Poke a quantum field and you will create an oscillation that usually dissipates outward, but configure things in just the right way and that oscillation will maintain its shape — just like Russell’s wave of translation. 
Because solitons are so stable, Lim believes they could work as a simplified toy model for the dynamics of bubble collisions in the multiverse, providing physicists with better predictions of what kinds of signatures might show up in the CMB. If his hunch is right, the expanding walls of our bubble universe are much like solitons.
Me: I've long been attuned to odd connections between seemingly unrelated topics, but this one really stretches far. I'm impressed.

* - Fixed my misspelling of the author's name.

Thursday, November 13, 2014

U.S.-China climate … thing

A lot of our political discourse seems to be people playing their predictable roles without expending much thought. The debate about the U.S.-China climate announcement is a case in point. Democrats are hyping it. Republicans are denouncing it (seeing it as part of a "war on coal."). Neither side has much incentive to notice the considerable limitations on its significance; which are, however, sketched out in a post by Jack Goldsmith, a law professor. Excerpt (with emphases from original):
Here the two sides do not promise to, or state that they will, reduce emissions by a certain amount. Rather, they state only that they intend to achieve emissions reductions and to make best efforts in so doing. Whether and how the goals expressed in these intentions will be reached is left unaddressed, and one nation’s intention is not in any way tied to the other’s. Nor would it be a violation of the “announcement” if either side’s best efforts fail to achieve the intended targets. As we have seen with a lot with climate change aspirations, intentions are easy to state, and they change over time. The key point is that this document in no way locks in the current intentions. In fact it creates no obligations whatsoever, not even soft ones (except that, in a different place, both sides “commit” to “reaching an ambitious … agreement” next year, an empty commitment). It is no accident that the document is called an “announcement” and not a treaty or pledge or even an agreement.
Me: I've long thought some kind of U.S.-China arrangement could be important, given the centrality of those two nations to carbon emissions and international trade, and given how hard it is to get any kind of multilateral agreement. But still, what's been achieved here is nothing remotely like, say, a bilateral agreement to put a price on carbon emissions (not surprisingly, as something like that would require legislation on the U.S. side, however much it might be imposed by fiat in China). The back-and-forth over this deal (which Goldsmith plausibly puts in quotes: "deal") is more about people displaying their ideological identities than anyone actually having much reason to exult or despair.

UPDATE: A different take, from Christopher Flavelle: "Obama Outmaneuvers Republicans on Climate Change."

UPDATE 2: Tyler Cowen: "The announced deal is little more than a well-timed, well-orchestrated press release."

Monday, November 10, 2014

Climate solutions

"Conservatives don’t hate climate science. They hate the left’s climate solutions," by Chris Mooney. About a new study that gives more evidence of how views on science can change depending on the policy prescriptions offered (and which discusses gun control as well). And all the more reason to expect climate politics in the coming decades to look very different from how it does now. (After much time has been wasted.)

Brad Thor redux

I'm glad to see, in looking at this blog's incoming traffic, that Quicksilber ranks high (#3 currently) in search results for: brad thor conspiracy theorist nutjob. Here's the post that accomplished this: "Fact checking a novel: Brad Thor's Hidden Order." Apparently I'm not a fan.

Posting may continue to be light in near term.

Wednesday, November 5, 2014

Post-election reading

Recommended reading: "Why the GOP Blowout Is So Scary for Democrats," by Peter Beinart. Short answer: because a more moderate Republican Party is emerging. Excerpt:
...there is one big takeaway from tonight’s Republican landslide that should worry Democrats a lot: The GOP is growing hungrier to win. 
It’s about time. As a general rule, the longer a party goes without holding the White House, the hungrier it becomes. And the hungrier it becomes, the more able it is to discard damaging elements of party orthodoxy while still rousing its political base. Between 1932 and 1952, it took Republicans five election defeats to convince their partisans to rally behind Dwight Eisenhower, who accepted the New Deal. Between 1980 and 1992, it took Democrats three defeats to convince their base to get behind Bill Clinton, a former head of the centrist Democratic Leadership Council who supported cutting taxes and executing murderers. 
In 2008 and 2012, Republicans couldn’t pull this off. Party elites backed John McCain and Mitt Romney, both of whom had records of bipartisan achievement and ideological independence that might have made them attractive to swing voters. But McCain and Romney faced so much hostility from the GOP’s conservative base that in order to win the nomination, and then ensure a decent base turnout in November, they had to repudiate the very aspects of their political identity that might have impressed independents. McCain, who had once called Jerry Falwell and Pat Robertson “agents of intolerance,” made another such agent, Sarah Palin, his running mate. Romney, who given his druthers would likely have supported comprehensive immigration reform, instead demonized illegal immigrants to curry favor with the GOP base. 
This year has been different: GOP activists have given their candidates more space to craft the centrist personas they need to win.
Me: I hope that's correct. Read the whole thing.

Tuesday, November 4, 2014

Social Security webinar note

Click here for information about a webinar I'm doing Nov. 5 with economist (and onetime presidential hopeful) Laurence Kotlikoff on "How to Work Social Security into Your Clients' Retirement Portfolios." That's in my capacity as senior editor at Research magazine, which is aimed at financial advisors (and which has no responsibility for Quicksilber, my personal blog).

One political note

Lack of time prevents me from spending much time blogging about the midterm elections (or much else) right now, but I will note that the congressional race in my (Republican-leaning) corner of New Jersey appears to be a real contest, with incumbent Republican Scott Garrett running ahead of Democratic challenger Roy Cho but not so much as to be assured of victory. In my area, it's easy to find lawn signs for either candidate, and the Cho campaign has wisely emphasized a message of "Moderate Republicans Support Roy Cho." I wrote about the objectionable Garrett here and here. Go Cho--and if you win, I strongly advise you to live up to those "moderate Republican" signs.

Friday, October 31, 2014

SpaceShipTwo implications

The crash of SpaceShipTwo in a test flight reminds me of these words a few years ago from Paul Spudis:
But what will happen to a commercial space tourism market after the first fatal accident? New Space advocates often tout their indifference to danger, but such bravado is neither a common nor wise attitude in today’s lawsuit-happy society (not to mention, the inevitable loss of confidence from a limited customer base). My opinion is that after the first major accident with loss of life, a nascent space tourism industry will become immersed in an avalanche of litigation and will probably fully or partly collapse under the ensuing financial burden. We are no longer the barnstorming America of the 1920’s and spaceflight is much more difficult than aviation.
Me: And this tragic failure of a suborbital test flight, of course, occurs even before commercial space tourism has really gotten anywhere. That industry has been slower to emerge than many expected a decade ago, and this sure isn't going to speed it up.

Monday, October 27, 2014

Paying for immortality

My latest at Research magazine involves how long people will live in 2030 and how long their money will last. I interview Joel Garreau about his four scenarios for longevity. Excerpt:
Small Change. In this scenario, technological advances have only modestly altered current trends in lifespans and health outcomes. Leading-edge baby boomers alive in 2030 are octogenarians and often infirm. Their kids who are in their 40s can expect to live into their 80s but face a familiar decades-long decline in health. Medical costs continue to skyrocket. According to Garreau, this is “the official Washington future regarding aging—the one many policymakers expect.” 
Drooling on Their Shoes. In 2030, under this scenario, technological advances have increased lifespans while doing far less to improve health in later life. Octogenarian boomers face decades of frailty and dementia; suicide rates among the aged have jumped. Health care costs are even more burdensome than in Small Change, increasing budget turmoil and intergenerational tension. 
Live Long and Prosper. Information technology has revolutionized health care while reducing its costs, in this 2030 scenario. Octogenarians remain active, thanks partly to what Garreau calls “Google Medicine,” a toaster-sized home appliance that analyzes spit samples to detect health changes. The first person who will live robustly to 150 is entering adulthood. Hospitals have become primarily for the less affluent, and tech-driven obsolescence threatens many health care institutions. 
Immortality. In his last scenario, Garreau raised the possibility of lifespans of indefinite duration. “Immortality is not as crazy as it sounds,” he wrote. Sufficient tech advances could boost life expectancy by one year each year, and “you have something that looks like immortality for some people.” Boomer octogenarians in 2030 have “too many hard miles on their chassis” to fully benefit, but younger people may have trouble imagining the onetime prevalence of sickness and death.
Whole thing here. My review of Garreau's Radical Evolution: The Promise and Peril of Enhancing Our Minds, Our Bodies -- and What It Means to Be Human is here.

Tuesday, October 14, 2014

Superintelligence, simulations, etc.

There's an interesting review of Nick Bostrom's Superintelligence: Paths, Dangers, Strategies at the website of the Institute for Ethics and Emerging Technologies, by piero scaruffi (whose name appears in lower case). I haven't read Bostrom's book, though I have been keeping tabs on the subject (see here and here) and found scaruffi's skeptical take on the dangers of AI intriguing. I then went to scaruffi's own site, and from now I will no longer worry, as I sometimes have, that my own blog incorporates an unduly broad range of interests; it's nothing compared to scaruffi, and I say that respectfully.

On another Bostrom-related note, I was a bit disappointed by Seth Shostak's piece "Is Life an Illusion?" which is an uncritical take on Bostrom's ideas about living in a simulation. I would've expected Shostak, who's spent decades contemplating probabilities involving alien life, to have something more sophisticated to say about efforts to calculate whether we are characters in a computer game. Years ago, I expressed some reasons for skepticism about that subject, which strike me as still making sense. (I don't, however, claim to be up to date on the technical debate over the simulation argument, and I see that Bostrom in 2011 co-wrote a "patch" for his original case.)

UPDATE: "Elon Musk: Robots Could Delete Humans Like Spam." Strikes me as not a compelling analogy, given how difficult it is to get rid of spam.

Thursday, October 9, 2014

Cosmic books

Current reading: The Copernicus Complex: Our Cosmic Significance in a Universe of Planets and Probabilities, by Caleb Scharf. So far it's quite interesting, and I have high expectations based on Scharf's work that I've read previously.

I also recently ordered and received Lee Billings' Five Billion Years of Solitude: The Search for Life Among the Stars, something I ought to have done a year ago and was reminded to do now by Billings' winning of a 2014 AIP Science Communications Award.

Sunday, October 5, 2014

Clinton history travels

Here are my son DeWitt and my wife Brooke at Fort Montgomery, in upstate new York, today, watching a reenactment of the battle where their direct ancestor James Clinton and his brother George Clinton fought against their distant relative Henry Clinton. Grant Miller, manager of the Fort Montgomery State Historic Site, is narrating the action.

Fort Montgomery 10-5-14
And back in August we visited the Syracuse area, where I continued my Erie Canal book research. Dan Ward, curator at the Erie Canal Museum, showed us around the museum as well as Camillus Erie Canal Park, which has impressive remnants of Clinton's Ditch as well as the Enlarged Canal. We also made a preliminary visit to the Chittenango Landing Canal Boat Museum.

DeWitt Clinton portrayal at Erie Canal Museum

Sign at Camillus Park
1842 Nine Mile Creek Aqueduct, restored in Camillus Park
Dry dock at Chittenango



Thursday, October 2, 2014

Climate-related readings

Recommended: a Bloomberg View series of editorials on carbon taxes, summarized here: "Doubt Climate Change? Then Support Carbon Taxes." Also recommended: "How to love uncertainty in climate science," by Tamsin Edwards, a particle physicist turned climate scientist. And: "The Left vs. the Climate," by Will Boisvert, at The Breakthrough (published by the Breakthrough Institute). Also see: "The Musk Family Plan for Transforming the World's Energy," by Christopher Mims at WSJ.

We're in the early stages of the long-term climate politics turnaround I predicted some months ago. That's when the technological and market-oriented measures that would actually reduce climate risks become anathematized by the left as too large-scale and industrial, and are picked up--albeit all too hesitantly and reluctantly--by the right; I began scribbling out how an astute GOP politician might talk about all this a few years ago at the often-ahead-of-its-time FrumForum.

NJ Senate race revisited

Some time ago, I mentioned Jeffrey's Bell's emergence as GOP Senate candidate in New Jersey, expressing approval of his credentials as policy wonk but wariness of his apparent intention to advocate a gold standard and make it the centerpiece of his campaign.

He has indeed done so, as evidenced by this WSJ piece, "Jeff Bell Takes on Cory Booker and the Fed." If we were living in a time of high and rising inflation, such as the 1970s, I could understand the focus on extremely tight money and how to impose a straitjacket that could keep policy tight. Given that this bears no resemblance to the current situation, I can only see it as an example of a time warp in the thinking of some conservatives and free-market types. However, I take issue with Cory Booker's riposte that Bell "wants to take us back to the '70s," when as the same article points out the last vestige of the gold standard was abandoned in 1971.

Monday, September 22, 2014

Expecting more of Neil deGrasse Tyson [updated]

I'm a fan of Neil deGrasse Tyson and plan to be in the audience watching him speak at a conference in November. In the conflict of "conservatives vs.nerds," in which he is an extremely high-profile representative of the latter, I have stated my overall sympathy for the nerds. With regard to many of the recent complaints, mainly emanating from The Federalist, about inaccuracies by Tyson, I find most of the allegations of minor significance (about headlines involving averages, or exact numbers of grams discussed in some jury duty). But Tyson's evidently fake story about a supposed George W. Bush quote in 9/11's aftermath requires an explanation and, if it is fake as it strongly seems to be, an apology. Tyson's silence on this matter so far should be discouraging to anyone who admires him.

UPDATE: The video of the Bush story.


UPDATE 9/25: A crock of a piece by John Aziz at The Week: "Earth to climate-change deniers: Neil deGrasse Tyson's errors won't help you." Includes this gem of a "to be sure" statement:
To be sure, science is about facts, and a public advocate for science shouldn't play fast and loose with the facts, even in the interests of a snappy presentation. This will inevitably invite criticism. Tyson needs to check carefully, in the future, that the quotes in his anecdotes are factual and not a figment of his imagination. And he should apologize to those who he has misquoted.
Me: How nice. Followed immediately by this:
But at the same time, it should be said that none of Tyson's errors amount to methodological or factual errors in published scientific papers.
Me: It should be said! And what a fantastically low standard for well-known scientists to follow! And how does Aziz know that Tyson's Bush story was an "error" as opposed to a deliberate fabrication, especially when Tyson won't address it? A defense like this makes the defended look worse.

UPDATE 1:06 PM: And I just noticed this tweet from Aziz:

Which accentuates my view that Aziz's article is disingenuous posturing. When you "concede" something by wrapping it in an attack on the critics you're supposedly conceding to, and trying to downplay the significance of what you're conceding, you are engaging in the empty tribalism that passes for so much of political discourse these days.

UPDATE 9/28: An admission of error, to a degree, by Tyson, made in the comments of two Facebook posts. He says he "transposed" the quote from just after 9/11 to after the shuttle Columbia disaster. He doesn't mention that he changed the wording of the quote as well as its context and gave it a meaning it did not have. But it looks like this is far as he's going to go. A disappointing performance. Case closed.

UPDATE 10/2: Tyson's statement on this matter. While it still seems like an attempt to downplay it, there is an apology in there. It'll do.

Tuesday, September 16, 2014

Space mining update

Recommended: "Mining in the Last Frontier," by Glenn Reynolds, about a bill now under consideration, known as the Asteroids Act. Excerpts:
The Asteroids Act is short and simple. After instructing the president and all agencies of the U.S. government to use their powers to facilitate space exploration and exploitation, it provides that "Any resources obtained in outer space from an asteroid are the property of the entity that obtained such resources, which shall be entitled to all property rights thereto, consistent with applicable provisions of federal law." In other words, if you mine it, you own it.
...
Things here on Earth aren't going so well at the moment, but we're actually in the midst of tremendous progress — most of it by private companies — with regard to human activity in outer space. The Asteroids Act is a significant step in taking things to the next level. I hope that Congress passes it.
Me: Here's hoping. I've been interested in this sort of thing for a long time, since well before this Reason piece I wrote in 1998. Sooner or later some broader framework will be needed (as I sketched out in Reason), when it comes time for, say, building hotels on the moon or other things that are not just about extraction and asteroids. Still, the Asteroids Act is a good step in the right direction (up).

UPDATE: For a different perspective (though not specifically about the Asteroids Act), see "Moon First—Mine the Asteroids Later," by Paul D. Spudis.

Monday, September 15, 2014

Mideast hall of mirrors (updated)

Who knows if anything the Iranian government is saying is true? As in this:
Iranian Supreme leader Ayatollah Ali Khamenei, speaking on Iranian state television, said his government privately refused American requests for cooperation against the Islamic State group, warning that another U.S. incursion would result "in the same problems they faced in Iraq in the past 10 years."
Or, to get it more directly:
If true, it's a failure for U.S. diplomacy, but also not very smart on the part of the Iranians. Not just because ISIS poses an obvious threat to Iran's interests, but because there's a whole other war waiting to happen sooner or later, and here was a chance to help avert it. Pascal Emmanuel-Gobry argued a few days ago that war between Iran and Israel is all but inevitable (and put the blame largely on the Obama administration, for its actions in Libya that showed that giving up your WMD is a mistake).

I don't tend to believe in things being "all but inevitable" but certainly that Israel-Iran war scenario is only made more likely by Iranian unwillingness to cooperate even against a common, profoundly evil enemy. It undercuts the "rational actor" theory that's offered for not worrying too much about Iranian nukes. Then again, who knows if anything the Iranian government is saying is true?

UPDATE 9/18: Iran's foreign minister Mohammad Javad, speaking in New York yesterday. I've only had time to watch part of it so far, and will watch more later.


UPDATE: Watched much of it, including the end. Many interesting things, but the ending wasn't particularly in keeping with his "new thinking" theme:

Tuesday, September 9, 2014

The climate-foreign policy nexus [updated]

Here's some dreary news:
Levels of heat-trapping carbon dioxide in the atmosphere rose at a record-shattering pace last year, a new report shows, a surge that surprised scientists and spurred fears of an accelerated warming of the planet in decades to come. 
Concentrations of nearly all the major greenhouse gases reached historic highs in 2013, reflecting ever-rising emissions from automobiles and smokestacks but also, scientists believe, a diminishing ability of the world’s oceans and plant life to soak up the excess carbon put into the atmosphere by humans, according to data released early Tuesday by the United Nations’ meteorological advisory body.
Such information gets only a fraction of the attention it deserves, in no small part because many people have convinced themselves there's no problem. Amid the current international turmoil, climate change will probably get even less attention than it typically does. There is a tragic irony there, in that foreign policy problems and environmental problems are not unrelated; on the contrary, they are intimately connected by the nexus of fossil fuels.

Civilization's heavy reliance on fossil fuels is a key contributor to climate change, through the mechanism of the greenhouse effect--and at the same time is a key contributor to geopolitical trouble, through the mechanism of revenues to trouble-causing states and terrorist groups. Putin's Russia and socialist Venezuela are buoyed by fossil fuel revenues, as are numerous bad actors in the Middle East. (Fossil fuels also cause environmental and geopolitical problems in other ways, ranging from oil spills to the need to keep supply lines open by policing the Persian Gulf with aircraft carriers.)

Reducing fossil fuel reliance would make sense even if there were no climate change problem; and is an imperative given the climate issue. Lamentably, recognition of the interrelated nature of these problems is scant across the political spectrum. On the right, objection to supposed "alarmism" about the climate blinds many to fossil fuels' relevance to national-security threats that are otherwise perceived as pressing. On the left, environmental alarm is intense, but expressing concerns about fossil fuel revenues to malefactors tends to be avoided as so much saber-rattling. (The concern that climate change itself is a national security threat gets play instead, and while it is valid, it is by and large a longer-term consideration than what enemies are doing with fossil fuel revenues right now.)

Occasionally, there are hints of some concordance between "national security hawks" and "climate hawks," as they have been dubbed, but the friction of divergent world views has prevented anything like a meaningful coalition from developing. Such a coalition might press for a carbon tax and stepped-up renewable energy research, citing the full range of reasons such things make sense (including fiscal ones). Thirteen years after 9/11 and facing a new Middle East war, even as carbon continues to build up in the atmosphere and oceans, it's high time for such a coalition to take shape.

UPDATE: An interesting piece: "The Republican Party's Secret Stance on Climate Change."

UPDATE 9/10: Just came across this from a few days ago: “I don’t think we really want a commander-in-chief who’s battling climate change instead of terrorism.”-- Rand Paul. Note to self: Never vote for Rand Paul. UPDATE: All the more reason.

Foreign policy update

I read this Robert Kagan piece "America's Dangerous Aversion to Conflict" with initial interest, followed by growing boredom. Analogies to the 1930s are such a stock part of conservative foreign policy rhetoric that it's a wonder there's no app for them. Some wording about Nixon-Kissinger foreign policy being "fatalistic" also struck a tinny note. (That policy was in fact quite activist and creative, which is basically the opposite of fatalistic.) I recently expressed my disagreements with the ill-considered and poorly argued non-interventionism at Reason, but Kagan's essay is a good reminder that neoconservatism has its own formidable blinkers, as Jacob Heilbrunn points out.

What the U.S. needs is to be smarter than its enemies, or at least not manifestly dumber, and to have what's sometimes called, a bit pretentiously, "grand strategy." That strategy should include, sometimes, making common cause with enemies, against worse or more pressing enemies, and thus making judgments about which enemies can potentially be given a more benevolent status. Insofar as the U.S. is now working with Iran, or will do so, that reflects a belated recognition that sometimes governments that hate each other still have reason to work together. In the aftermath of 9/11, that recognition went by the wayside, with unfortunate consequences spilling down to the present.

Inasmuch as we do live in a period remotely similar to the 1930s, that's all the more reason why we need to be building up alliances, de facto and de jure, including in some cases with traditional enemies. If there's anything that's "fatalistic," it's assuming that this can't be done.

UPDATE: "Obama Should Play Nixon and Go to Iran."

UPDATE: "2014 Is Not 1931," though it is true, as has been noted, that Chamberlain wasn't PM in 1931 either.

Friday, September 5, 2014

Contemplating foreign policy at Reason

I've been reading the non-interventionists at Reason magazine, trying to assess what their preferred non-interventionist foreign policy would actually consist of. Here's Sheldon Richman: "Let's Have Some Honesty and Realism at the NATO Conference," explaining that the fault for the Ukraine crisis belongs to the U.S. and the West for having expanded NATO years ago, and concluding:
Yet another manufactured crisis — costing over 2,000 lives. It could be brought to a speedy end if Barack Obama would give the word.
Me: What word? What is Richman asking Obama to do? It's only implied, but apparently the answer is to expel Eastern European countries from NATO. Or is it to disband NATO altogether? (The latter would effectively follow from the former at this point anyway.) And if that means more countries would fall under the domination of an aggressive dictatorship, we should be willing to accept that, because--libertarianism. But how come a piece demanding honesty avoids saying any of that?

Also, here's Jacob Sullum complaining--rightly--that Rand Paul has flip-flopped on confronting ISIS. True enough, and one of the many dispiriting things about a Rand Paul presidency would be watching him engage in endless cartwheels between his father's positions (on domestic and foreign policy alike) and political expediency or, I would argue in some cases, sanity. Sullum states plaintively: "Paul still has not explained why the problem of ISIS is one the U.S. has to solve."

What exactly would have been involved in the U.S. deciding it wasn't going to participate in a response to that problem? (It's a strawman to complain the U.S. is trying to solve that problem singlehandedly, though admittedly some hawkish rhetoric plays into that misconception.) Let's see. In early August, the U.S. could have done nothing to help the Yazidis, beseiged and starving on a mountaintop, or to arm the Kurds, whom ISIS was attacking, or to prevent ISIS from controlling the Mosul Dam (and breaking it to cause a massive flood if they so chose). Humanitarian disaster on a vast and growing scale? Not our problem, because--libertarianism.

If that policy had been followed, perhaps ISIS would've been too busy slaughtering its local enemies to turn its attention to the U.S. anytime soon. Perhaps they would have refrained from murdering two U.S. journalists who were already in its captivity. Why is murdering Americans even a casus belli?, Sullum asks. I would suggest that every U.S. administration since that of George Washington, who warned against "entangling alliances," would regard it as such, though it is true that not every murder by some despicable group begets a U.S. military response. Some contextual thinking is required.

In this case, for example, we are talking about a terrorist group and rapidly growing self-declared state that is an even more brutal offshoot of a terrorist group that has already attacked the U.S.; and which controls a large swath of territory and has major funding, including oil revenues; and exerts an ideological appeal over alienated Western thugs and sociopaths and attracts recruits with each battlefield success. Imagine if, say, in 1944 some new Nazi movement had arisen, dismissive of Hitler as not aggressive enough, and retaken the Germany-France borderland after our troops had moved through. Would that have been not our fight?

And here's Nick Gillespie a few days ago:
Despite the claims of hawks and ISIL itself, the terrorist group is hardly an existential threat to the West any more than al Qaeda was. It can and should be contained and squeezed down everywhere as much as possible (this is not something that mandates either an interventionist foreign policy or expansive security state at home).
Me: How do you contain them and squeeze them down? The non-interventionist way of doing that remains unclear to me. And if they're not an "existential threat," are they some other kind of threat? And if they become a larger threat--with say multiple cells in the U.S.--will we then be hearing it's too late to do anything about it?