I can think of several reasons why Barack Obama might have been reluctant to go ahead with a Moscow summit meeting with Russia’s Vladimir Putin. Moscow’s refusal to repatriate Edward Snowden, the former National Security Agency contractor responsible for leaking some of Washington’s most closely held secrets, comes well down the list.

There is nothing good to be said about the present regime in the Kremlin. Deeply repressive and corrupt at home, it is habitually disruptive if not destructive in its approach to international relations. Russia is a great power on the cusp of serious decline, kept afloat for now on a sea of hydrocarbons. It is in thrall to a kleptocracy unable or unwilling to separate the national interest from personal gain. Mr Putin’s answer is to alternate between playing the victim of western perfidy and pretending, ridiculous though it seems, that Russia remains a superpower on a par with the US.

So you can see the reasoning in the White House. Russia continues to sustain the murderous regime of Bashar al-Assad in Syria, has refused to seriously engage about further nuclear weapons reductions and acts for much of the time as if the world is still living through the cold war. With the fall of the Berlin Wall and the collapse of Soviet communism, Russia lost an empire. Mr Putin has never got over it. Sergei Lavrov, his foreign minister, often seems to inhabit a fantasy where Nato is plotting war against Russia.