How dangerous is Vladimir Putin’s Russia? That was the question that Rex Tillerson was grappling with, just hours before he was sacked. The former US secretary of state told reporters: “We’ve seen a pivot on their part to become more aggressive. And this is very, very concerning to me?.?.?.?We don’t fully understand what the objective behind that is.”

The question of Russia’s real intentions is all the more urgent because, to nobody’s surprise, Mr Putin has just been declared the victor in the presidential election, and is set for another six years in the Kremlin. Normally, a president entering his fourth term in office is a known quantity. But the Russian leader seems to be becoming more reckless and confrontational with the passage of time.

Russia’s deployment of a deadly nerve agent on the streets of the UK is a new and dangerous departure. The US government has just accused Russia of scoping out possible attacks on America’s critical infrastructure. In a recent speech, Mr Putin boasted of a new generation of “invincible” Russian nuclear weapons that could devastate America, and used videos to illustrate his threats. And he closed his re-election campaign with a flag-waving rally in Crimea, the territory that Russia seized from Ukraine in 2014.