Thomas PM Barnett on his blog argues that will NEVER happen! Well perhaps not but am guess that a nuclear capable, delivery capable N.Korea or Iran might well spark proliferation in fact or announced. Hope I am around in 2030 but only to see Tom right and my deceased friend at CIA wrong.

Canada could do it. Sweden could do it. Germany, Switzerland, Netherlands….it just isn’t that hard. Remember that South Africa did it without testing in the late 1970s. Japan has enough PU sitting around that while it is an esoteric argument about exactly how quickly they could go nuclear (one year to three years…), no one doubts it.

The first nuclear test was the type dropped on Nagasaki. The Hiroshima bomb was never tested because everyone assumed (correctly) it would work.

The largest barriers for nation states is constructing an indigenous fissile material production capability (see Iran now and Pakistan use of illicit technology acquisition earlier). Next is a delivery system–in other words not simply weaponizing their material but making it small enough to fit on a ballistic missile since large bombers are generally unreliable systems for immature nuclear powers. (Triggers aren’t so hard…we and others figured it out decades ago…).

The largest barrier for terrorists is simply acquisition of the fissile material. They can’t make it so they need to acquire it. Especially if they get HEU, the barriers to making a crude but working weapon are large but not insurmountable. (Waiting for J. to chime in against the threat in 5, 4, 3, 2, …).

The Thorium question I’m not so sure about, but give me a few days and we can discuss offline. I have enough faith in the market system to believe that there must be some intrinsic issues with using Thorium for power production that led to the reliance on uranium and Pu.

Your last question is not so easy to answer. What do you mean by “weapons grade?” The current definition of weapons grade or that is actually use-able in a weapon? For example, today weapons grade HEU means 90% or above. But the bomb dropped on Hiroshima used uranium enriched to something in the 80s. And a weapon could be made with less…it just takes a lot more material as you go down the enrichment scale. In addition, weapons grade material from Russia has been blended down and used to produce electricity in the U.S. You also have the issues surrounding material used in research reactors plus that reprocessed for nuclear power use.

One estimate of what you are looking for:
Amount of HEU required to make a crude nuclear bomb: 25 kg
# Global stockpile of HEU: 1,600,000 kg
# Amount of Pu required to make a crude nuclear bomb: 8 kg
# Global stockpile of separated Pu: 500,000 kg
(http://belfercenter.ksg.harvard.edu/publication/20057/nuclear_terrorism_fact_sheet.html).

This leads me to believe something is working. That something probably involves the substantial effort and expense involved in acquiring or producing the preferred fissile materials U235 and Pu239, not to mention the trigger and launch capabilities. (Yes, I realize that a very destructive weapon could be packed inside a common shipping container and deployed almost anywhere without much sophistication.)

Had the U.S. not joined its nuclear power production and atomic weapons programs at the hip, we might well have seen this whole story take a different turn. Thorium, in particular, is a far less dangerous and more plentiful material, which has proven efficacious as a reactor fuel in power production applications. Investing in this technology rather than developing a new generation of conventional reactors (if this comes back into vogue) might help maintain the status quo while allowing others to develop and deploy this alternative energy technology without the same risk of nuclear proliferation.

Does anyone reading this blog know (roughly) the total quantity of weapons-grade material currently in existence anywhere that has not already been weaponized, i.e., used to produce an actual weapon that is in the stockpile of a nuclear nation? I am assuming, perhaps incorrectly, that the available supply of weapons-grade fissile material is not too vast, and could be rather easily secured if its location could be verified.

MAD works against the first case, but not against the second. All the US has to do in the first case is explain to Iran/North Korea/etc that any offensive use of nuclear weapons against the US or our allies WILL result in nuclear weapons being used against the aggressor, accompanied with a photo-book of Hiroshima and Nagasaki, to remind them that the US is the only country that has every used nuclear weapons.

The second case (Al Qaeda, et al) will not be as amenable to reason. They will off a nuclear weapon (if they acquire one) because they can’t be similarly targeted, and besides, they’ve got God, Allah, or the Flying Spaghetti Monster on their side.

Unfortunately, the one thing we can’t do is get rid of ALL nuclear weapons — prohibition doesn’t work, and the science and engineering are too well-understood by too many people. Anyone who can get their hands on enough plutonium and who has the resources to support a 3-5 year engineering effort should be able to build fission weapons. (Thankfully, fusion weapons are still out of the reach of the non-state players).

From that I conclude that we need to be spending serious resources to improve FEMA’s capabilities for responding to a nuclear incident.

For some background thinking and info you can review some more of my thoughts and conclusions at my blog:
http://vlg338.blogspot.com