Can America Trust Its Aging Nuclear Arsenal? by Steven Koonin.
To ensure future deterrence, the U.S. needs to have a well-maintained nuclear-weapons “complex,” as we in the field call it—that is, the array of laboratories and specialized industrial plants within the Department of Energy that keep our nuclear arsenal in working condition. That complex faces serious challenges today and could begin to break down within the next decade, with dire ramifications for the security of the U.S. and the world. …
I started to learn about nuclear weapons in 1972 as a 20-year-old graduate student working at Los Alamos National Laboratory. What struck me most, upon first seeing a nuclear weapon up close, is how small it is. The basic physics of the device packs tremendous energy into a compact space: A conventional explosion compresses plutonium to a critical mass, a chain reaction amplifies the energy 100,000 times, and then there’s another 10- to 100-fold amplification as the X-rays produced cause additional nuclear reactions. It is a tightly linked chain of amplification, and if any one of the stages fails, the weapon fizzles. …
Engineering plays an important role. Nuclear explosives must work in a range of extreme conditions, must not go off unintentionally and must be secure, making a weapon inoperable were it to fall into the wrong hands. The design of these devices is very sophisticated, and small modifications can make a big difference in the amplification chain.
Do the US weapons still work? I heard that even in the days of the USSR it was widely thought only 90% of US weapons would actually work, but maybe only 40% of the Soviet ones. Hence the huge overkill and redundancies.
But much has changed since my days as a graduate student. It has been 25 years since we last performed a nuclear test, the newest designs in our stockpile date from 40 years ago, and some of our key research and maintenance facilities are now more than 60 years old. The crucial question today is what it will take for us to continue to have confidence in these systems. …
Since 1992, when the U.S. adopted a moratorium on nuclear testing, the challenge has been to assure that weapons in the stockpile can sit for decades — their metal parts corroding and plastic parts degrading — and still perform as expected. …
[Innovations have] let us make our weapons safer (with less sensitive explosives) and more secure (with the superior safeguards made possible by modern electronics). …
[T]here are now fewer than 50 designers qualified to assess our weapons, and the number with nuclear-test experience is diminishing rapidly. Younger would-be stewards of our arsenal are constantly tempted away by more lucrative opportunities doing more conventional work. …
Years of delays in replacing shuttered plants have left us without the ability to produce key weapons components. … As our weapons age beyond their intended lifetimes, we must also continually update and improve the experimental and computational facilities used for assessing them.
The US nuclear deterrent has played a major role in making the world relatively peaceful since WWII.
