The new nuclear threat

The cold war ended peacefully, and the deployed nuclear arsenals of the US and Russia have been reduced by nearly 90 percent, but we are not safer today—quite the reverse. After decades of building just enough weapons to deter attack, China is now aggressively modernizing and enlarging its small nuclear arsenal. Russia and the US are modernizing theirs as well with entire menus of new weapons. Activities in space are enlarging the global battlefield. Advances in missile technology and conventional weapons “entangle” scenarios of nuclear and nonnuclear war, making outcomes highly unpredictable. The risk of cyberattacks on command and control systems adds another layer of uncertainty, as does research on artificial intelligence that increases the prospect of accidents and the unintentional use of nuclear weapons. Arms control agreements that significantly limited the US–Soviet arms race are being discarded one by one. And from Russian efforts to destabilize America through social media attacks on its democracy, to Chinese bellicosity in the South China Sea and clampdown on Hong Kong, to erratic lunges in US foreign policy, there is deep and growing distrust among the great powers.

Yet the public isn’t scared. Indeed, people are unaware that a second nuclear arms race has begun—one that could be more dangerous than the first. Decades of fearing a nuclear war that didn’t happen may have induced an unwarranted complacency that this threat belongs to the past. A million people gathered in New York’s Central Park in 1982 to call for an end to the arms race in the largest political demonstration in US history. Today the prospect of nuclear disaster is barely noticed.