PERHAPS Partygate has at least one thing going for it. In normal times, the Government would be rightly castigated for getting caught up in a petty domestic row (albeit with serious implications) during a grave international crisis. Concerted action against a common threat takes immense effort, especially when played out against an unknown deadline. The Russian threat against Ukraine appears, however, to be of a different order. The Times on Tuesday quoted a Kiev resident, Mariana Zhaglo: “This threat has been present one way or another for eight years: ramping up troop levels, then taking them back again, was a regular practice both of the Soviets and the Russians. People here became familiar with the tension. I am the only one in my own social circles even talking about this crisis at the moment. My friends and neighbours are talking about where they will spend their spring and summer holidays.” The Russian press agency Tass quoted a Kremlin spokesman who described the rumours of a threatened “invasion” as “empty and unfounded”. More convincingly, the same report quotes the Ukrainian Defence Minister, Oleksii Reznikov, saying pretty much the same thing, i.e. that he had received no information so far indicating the possibility of a Russian invasion in the near future.

President Putin learnt long ago that an aggressive foreign policy stands him in good stead at home, where shaky economic conditions empower the opposition parties — or would, if their leaders were not in detention in Siberia. He is also aware, however — as are the bordering states — that an actual conflict could quickly turn Russians against him. Perhaps surprisingly, the shadow of Afghanistan looms over both sides of this stand-off. For Western nations, the fall of Afghanistan to the Taliban was a lesson in how swiftly, when they look the other way, things can go bad. This is a chief reason for the urgency in their actions and pronouncements.

For Russia, Afghanistan stands for something else entirely. The 1979-89 occupation was a costly humiliation that contributed directly to the fall of the Soviet Union in 1991. It drained the economy of vital funds, and its human losses — 15,000 killed, more than 50,000 injured — injected bereavement and political disaffection into the heart of the Soviet Union. Just as fatally, it inflicted losses on the satellite states (one quarter of the troops in Afghanistan were from Ukraine, of whom more than 3000 died) while at the same time exposing the Soviet Union’s military vulnerability.

For this reason, it might be just as well that Boris Johnson has other matters to distract him. Having been (briefly, thankfully) one of the UK’s worst Foreign Secretaries, he seemed earlier this week to have little more than bombast to contribute to the situation. It is one thing to remind President Putin of the cost of a possible incursion; it is another to offer public provocation, making it harder for him to scale his operations down. The situation on Ukraine’s border is perilous. Russia has made it so. But the Ukrainians, at least, see the value in playing it cool.

Paul Vallely: How the West should deal with Russia