August 29, 2004  ·  Richard Posner

Interesting comments, as usual; and since this is my last day as Larry’s guest blogger, I think I’ll limit myself to responding to comments. (Unfortunately, I can’t respond to all–and of course some comments are responded to very well by other commenters. I am impressed by the quality and interactive character of many of the comments.)

One commenter corrected my statement that the Copenhagen Consensus had ranked global warming last on the list of the world’s ills. For one thing, the list is very incomplete (more on that below). For another, what the conferees were asked to rank were solutions, not problems. They were given three solutions to global warming, including the Kyoto Protocol, and didn’t like any of them.

But what a weird procedure! Not to ask the economists to rank the best solutions they could think of, but instead give them the solutions and tell them to rank them. So by his choice of solutions, the organizer could pretty much predetermine the results.

Another commenter asked: what makes me think global warming is the world’s most serious problem? Nothing; but it’s not what I think. The Copenhagen conferees were given a short, rather eccentric, list of problems; they were not asked what they think the most serious problems are. The list includes not only malnutrition, AIDS, and malaria, but also such things as water purity and trade barriers. In that list, it seems to me global warming is the most serious problem, though it doesn’t follow that we should adopt either the solutions put to the conferees, or any other solution: that depends on costs and benefits. Global warming would be very costly to arrest, so maybe we shouldn’t do anything about it, although for reasons I can’t adequately explain here but are spelled out in my book, I think we should.

If I were asked to list the greatest threats to the world, I would include global warming, but would add bioterrorism, nuclear terrorism, nuclear proliferation, biodiversity loss, cyberterrorism, nanotechnology, artificial intelligence/robotics, and asteroid collisions.

Asteroid collisions? I anticipate teasing comments asking me whether I’m also worried about invasions of aliens from other galaxies. (I’m not.) In fact the probability of a catastrophic asteroid collision, while small, has a greater expected cost than the $4 million that is all that NASA is spending a year to map NEOs (dangerous near-earth objects, i.e., asteroids whose orbits intersect the earth’s orbit. For a good discussion, see the report of the Task Force commissioned by the U.K.’s minister for science. It was less than a century ago that an asteroid a mere 60 meters or so in diameter exploded over Siberia with the force of a hydrogen bomb. Fortunately, the only casualties, so far as anyone knows, were the local reindeer. Maybe the next asteroid will explode above Los Angeles, sparing the reindeer. Of course that’s unlikely; cities occupy a minute fraction of the earth’s surface. But a slightly larger asteroid, wherever it landed, could inflict tens or even hundreds of millions of casualties from tsunamis, fire storms, shock waves, and dense clouds of debris that could block photosynthesis and even trigger catastrophic global warming.

A survey of global dangers, ranking them by expected costs, and analyzing cost-justified responses (if any), would be a great project, and one in which economists would play a key role. The “Copenhagen Conference,” however, strikes me as a parody of such an undertaking.

  • http://pobox.com/~joehall/nqb2/ joe

    Here’s a disaster that is not given much credit — the prospect of war involving explosions in low earth orbit. In short: such a war could imprison us on the surface of the earth for many millenia. Read more here:

    We Need a Better Bullet Bucket
    http://pobox.com/~joehall/nqb/archives/000265.html

    (that is my old blog… click on my name for my new blog)

  • A.J.

    Judge Posner,

    Really enjoyed reading your posts. Have you considered starting your own Web Blog? Anyway, I think you deserve a Nobel Prize and the next appointment to the Supreme Court of the United States. I really admire you a lot. Take care. Come back soon!

    A.J.

  • Raoul

    Judge Posner,

    Thank you for your varied, insightful and entertaining posts. Global warming is considerably more of an immediate and sever danger than terrorism. Although, as technology enables individuals to be increasingly dangerous that may change.

  • Palooka

    Raoul,

    The technology ALREADY exists. For the most part, that technology requires the resources that only a state can garner. That’s exactly why targeting those like Saddam is an integral part of the war on terror–states which sponsor or encourage terror must know they will be held accountable.

  • Mojo

    Palooka;
    Iraq has never provided weapons of mass destruction to any terrorist group. There was no operational relationship with terrorists prior to our invasion. Iraq doesn’t have weapons of mass destruction and didn’t have any even in the past that were suitable for use by terrorists that would cause damage on a large scale. Even the administration has now changed their position on the justification for the war since this justification simply doesn’t hold water. (BTW, 9/11 was committed by transnational terrorists. They were given haven in Afghanistan, but weren’t actually a state-sponsored group.)
    I agree that state sponsors of terrorism should be held accountable. That means all of them, including our current allies. For example, our ally Pakistan’s nukes are a much bigger threat than Iraq’s “weapons of mass destruction related activities” were and Pakistan has directly sponsored and supported terrorists. Also, even the worst case scenario for a terrorist attack pales in comparison to the potential damage of an asteroid or comet strike or major global warming.

  • http://diaryofa1l.mikeshecket.com Mike Shecket

    Judge Posner:

    Hi, I’m a 2L at Ohio State as well as a U of C alum. I just wanted to say thanks for dropping by the blogosphere and giving a few of us a chance to exchange ideas with you. I’ve enjoyed reading many of your opinions; one that springs to mind is U.S. v. Marshall where Judge Easterbrook and yourself debate the finer points of LSD and legislative intent. That was pretty much the only case in the entire Legislation casebook that wasn’t totally boring, so thank you for that! Keep up the good work and come visit OSU sometime.

  • John

    Some interesting points. I criticised various aspects of the Copenhagen exercise here, here and here

  • Macneil

    Re: Asteroids. I saw one comment some post back asking if you were concerned about them. They point the poster was trying to make was that it seemed silly, but reading the commenter’s post I just had to think “how foolish.”

    I think when it comes to many issues some conservatives would rather keep their heads in the sand than do anything about it. Even though oil supplies are shrinking, I think part of the popularity of SUVs is due to the fact that people want a way of saying “I know the future is bleak, but it’s not going to affect *my* behavior.” It’s a reducto ad absurdum of sorts: just like how a conversation about vegetarianism always seems “off” when it is held around people eating meat. I think we all know it’s wrong to eat animals, and after the 1970s, we all know oil is a major problem. The problem is, culture has made it so normal that it can only take a very strong character to even say “enough,” let alone change behavior.

  • Joe

    “Cyberterroism”. The very term makes me cringe — not with fear but with annoyance. While it is true our computer networks are not well secured, and that most people have simplistic and incomplete mental models of computer networks, the actual risk has been exaggerated. It should rank nowhere near AIDS, global warming, nuclear proliferation or (physically violent) terrorism. The prefix cyber is misued. It’s a flag to me to know when someone is trying to sound important but not really understanding the issues they speak of.