This world view—a noxious compound of KGB cynicism and increasingly messianic Russian nationalism—propelled him into Ukraine. The idea that his adventurism will end in the Donbas is as naive as the theory that he would be satisfied when his troops wrenched Abkhazia and South Ossetia from Georgia in 2008. This week Mr Putin rattled his sabre at Kazakhstan, still ruled by the elderly Nursultan Nazarbayev: any succession squabble would be an opportunity. Estonia, Latvia and Lithuania, small, ex-Soviet countries, have Russian-speaking minorities of the kind Mr Putin has undertaken to “protect”. These Baltic states joined NATO in 2004. But what if a Russian-financed separatist movement sprang up, a Baltic government claimed this amounted to an invasion and its NATO allies refused to help? The alliance’s bedrock—its commitment to mutual self-defence—would be shattered.
Mr Putin’s revanchism must therefore be stopped in Ukraine. This week, en route to a NATO summit in Wales, Mr Obama visited Estonia to assure his Baltic allies of America’s backing. A brigade of American soldiers would be more reassuring still. NATO is set to approve a nimbler reaction force, with kit pre-positioned in Poland. But it is past time for the alliance to junk the undertaking it gave Russia not to base troops in the Baltics: that was made in an era of goodwill, which Mr Putin has trampled. The Europeans must do more to wean themselves from Russian gas, by diversifying supplies and introducing new rules and infrastructure to trade energy across the continent. Mr Putin is not a good commercial partner.
Eventually these measures may together force Mr Putin to rethink his recklessness, or encourage the Russian people and elite to think differently about him. There will be a price for the West too, of course. But as poor, benighted Ukraine shows, the price of inaction has always been higher.
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