Keeping the world safe when no one is in charge

International politics today feels like a collective sleepwalk into the abyss. Three trends are particularly alarming. Artificial intelligence is globalising and turbocharging old and new threats. Meanwhile, no state is strong enough to impose order. And, as in earlier periods of global crisis, geopolitical blocs are hardening, with international cooperation increasingly portrayed as weakness. Alas, there is ample reason to fear a repetition of the worst of history.