Wednesday, October 05, 2005
Fact. v. Fear on loose nukes
Fear of nuclear weapons worked very well in selling the Iraq War.
Now it's a product in the campaign to get Americans to surrender their liberties. Other entries in the product line are avian flu, hurricanes, secular liberal humanists, etc. But nothing sells quite as well as bringing our image of Hell to earth.
Nuclear weapons, or more broadly, the risks of the release of ionizing radiation are a very serious issue. The bombings of Hiroshima and Nagasaki, the radiation releases at the Chernobyl and Three Mile Island power plants, the increasing evidence that depleted uranium is a substantial public health risk, the risks of "dirty bombs" and "suitcase nuke"-- all of these are reasons to be concerned.
But without diminishing the problems of terrorism, realistically, we were in far more danger from ICBMs during the half century-long Cold War than we are from terrorists. In fact, we still are.
(continued in comments)
Understanding this requires getting into some details of nuclear weapons or, more generally, fissile material.
ReplyDeletePotential nuclear explosive materials are radioactive; they are [almost always] very dense, and therefore absorb certain types of radiation very well; and they can be fissioned. Therefore there are three basic ways of detecting them: "passive" detection of the radiation they emit; "active" detection of very dense objects in a package (such as with an X-ray machine), which then require further investigation; or "active" detection by irradiating the object and observing whether any fissions result.
Most uranium, manufactured from nuclear reactors, is contaminated with U-232, which emits a strong gamma ray and is relatively easily detected. Reactor grade plutonium emits both gamma rays and neutrons, and is easily detected. Other fissile materials, like Cobalt-60 or Cesium-137 are easily detected. However, the detector needs to be within a few hundred yards of the weapon. Closer, for smaller amounts.
Tests on one typical brand of portal monitors determined that in the absence of any shielding, the pedestrian monitors could detect 10 grams of weapon-grade HEU or a third of a gram of weapon-grade plutonium, while vehicle monitors allowing the vehicles to proceed through at 8 kilometers per hour could detect 1 kilogram of HEU or as little as 10 grams of plutonium.
Of course, if the material isn't shielded, it's very likely a pedestrian carrying weapons grade plutonium would develop symptoms of radiation sickness fairly quickly. 2000 rem is enough to kill within minutes. However, lesser effects, like nausea, vomiting, diarrhea, bleeding, spontaneously bursting into flame and the like tend to get one noticed.
Uranium would be easier to get through.
Stimulated detection and X-raying requires much closer proximity to the item. One can't use stimulated detection on humans, and repeatedly X-raying anyone except a known member of al Qaida would be counterproductive. These are only useful for point detection, as for example in a queue of cargo.
ReplyDeleteThe smallest possible suitcase nuke would actually be Olympic model
Unclassified "model" calculations carried out in 1990 to estimate the composition and weight of relatively simple implosion designs based on plutonium and HEU came up with diameters in the range of 18 inches and weights in the range of 300-400 pounds.
Now, this is fully assembled and assumes extreme design savvy. The actual amount of nuclear material is only a few pounds of that total. But functionally-capable "suitcase nukes" are not going to be carried around in suitcases by anyone less than an professional weightlifter.
Realistically, a terrorist group could produce a Hiroshima-type bomb equivalent to 10,000 tons of explosives.
This is a lot of tons, as the people of Hiroshima and Nagasaki can testify.
Let's run through the bullet points:
1. Detecting nuclear materials, even with all the trade we do, is feasible
2. Feasibility greatly increases if we can reduce/eliminate illegal immigration
3. Reducing/eliminating illegal immigration can only be done by raising wages in Latin America and Asia
4. Feasibility also greatly increases if we reduce loose fissile material.
5. Reducing loose fissile material would be greatly enhanced by ending Republican rule. These jerks have spent years fooling around on this issue.
6. Feasibility also greatly increases if we can persuade the rest of the world that we are not all jerks.
7. You are still in more danger of being blown up by an ICBM than by a terrorist. Iraq veterans have to worry about exposure to depleted uranium. All of these things are serious issues.
And here's the bottom line:
"They who would give up an essential liberty for temporary security, deserve neither liberty or security" --Ben Franklin
Don't let yourself get turned around.