The World’s Nuclear Guardrails Are Disappearing

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These dismal circumstances follow substantial advances in halting the spread of nuclear weapons. In the ’60s, the decade in which the most new nuclear states emerged (France, China, and unofficially Israel), John F. Kennedy predicted that there would be “15 or 20” nuclear powers by 1975. Today there are nine, a rate of about one to two entrants into the nuclear club per decade, with the latest being North Korea in 2006. The nuclear-security scholar Jim Walsh has noted that three-fourths of countries that were once interested in developing nuclear weapons ultimately chose not to do so, and that since the ’90s, more states have given up nuclear weapons than acquired them.

The number of nuclear weapons in the world, moreover, has dropped from more than 70,000 in 1986 to fewer than 14,000 today because of arms-control efforts. (That’s still enough, of course, to kill billions of people and envelop the world in a nuclear winter. When it comes to nuclear nonproliferation, progress is only heartening when expressed in relative terms.)

Most of the reductions in these weapons, however, occurred in the ’90s, and the pace of cuts has slowed ever since. We now live in a period when the barriers to acquiring nuclear weapons, a 75-year-old technology, are much lower than they once were. It’s also a time when, as James Holmes of the U.S. Naval War College once explained to me, there are more nuclear-weapons states “of different shapes and sizes … [and] different trajectories,” making the “geometry” of nuclear deterrence “far more complex and harder to manage” than during the comparatively symmetrical Cold War.

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Add to that the fading memory of the Cold War and fiercer competition among the great powers, and it’s no surprise that the guardrails on the world’s most destructive weapons are disappearing.

The past year may be remembered “as the turning point from an era of relative calm” to “the dawn of a dangerous new nuclear age,” Miller and Narang wrote last month in Foreign Affairs. The consequences could be “catastrophic.”

Uri Friedman is a staff writer at The Atlantic, covering national security and global affairs.