NUCLEAR, BIOLOGICAL AND CHEMICAL WEAPONS
June 9, 2013: There’s a furious debate going on within American intelligence agencies over whether Iran or North Korea have the ability to quickly produce a nuclear weapon that is compact and sturdy enough to be used in a missile warhead. Building such warheads is no easy task, as they must not only shrink their crude initial nuclear weapons designs but also make them rugged enough to withstand the stresses of takeoff and re-entry. These stresses are formidable and include a lot of vibration, heavy G (gravity) forces, plus changes in air pressure and radiation damage to electronics as the missile reaches a point near the end of the atmosphere (which absorbs most of that radiation before it hits the surface) and plunges earthward. There is a lot that can go wrong between the launch and moment when the nuke is supposed to detonate.
The optimists (who believe functioning missile warheads are attainable) believe that the larger (half ton and up) warheads of the North Korean and Iranian ballistic missiles are also roomy enough to limit the amount of miniaturization required. The optimists also believe that with modern computers it is easier to build accurate simulations of all this and quickly test designs. Also, over the last half century more stable explosives have been developed, eliminating a lot of the “unstable explosives” problems. The optimists also believe the North Koreans and Iranians are smart enough to pick the right answers out of the huge amount of published scientific research data on both fission and fusion bombs. This was assisted by the United States declassifying a lot of information on nuclear weapons technology over the past few decades. This material did not cover the latest developments but allows countries like North Korea and Iran, who are starting from scratch, a way to avoid a lot of basic technology problems. Then there is the more advanced tech that has reached the black market, provided by unemployed Russian scientists (or corrupt officials with access to that stuff), China (which officially and quietly assisted Pakistan), and corrupt Pakistani scientist A. Q. Khan, the father of the Pakistani nuclear bomb, who went into business for himself on the side once he created a working bomb for his homeland.
The pessimists point out the large number of errors the United States encountered while developing these smaller and more robust warheads and the number of problems the Russians were found (after the Cold War ended) to have encountered as well. The Russians had even more problems than America because they did not have as large a scientific, engineering, and industrial infrastructure as the United States.
One must also keep in mind that for half a century nations have refrained from testing complete systems (missiles armed with nuclear warheads) in actual launches. Detonating warheads in the atmosphere was outlawed (for good reason) long ago and even the renegade developers (like North Korea and Iran) have done their weapons testing underground and hoped that their warhead designs would work. You can test warhead designs without the nuclear material, but not much of that has been detected from North Korea or Iran and that type of testing is still not perfect.
The pessimists caution that these two nations have a reputation for stumbling in the development of high tech and it’s unlikely that they will suddenly get much better just because they are working on nukes (which are inherently more complex). Ultimately North Korea and Iran may simply rely on the fact that detonating a nuke in a cave and building long range ballistic missiles may be sufficient to frighten the neighbors into compliance.