Both sides are contemplating escalation in the row over an assassination attempt on a former Russian spy-turned-mole in Salisbury earlier this month. The UK’s top diplomat took accusations against Russia a step further than Theresa May did earlier in the week, who said it was “highly likely” Russia was behind the nerve-agent attack. This morning, Boris Johnson accused Vladimir Putin of personally ordering the hit:

British Foreign Secretary Boris Johnson says it’s “overwhelmingly likely” Russian President Vladimir Putin ordered the use of a nerve agent against a former spy in the English city of Salisbury.

Prime Minister Theresa May has said it’s “highly likely” the Kremlin is responsible for the attack on Sergei Skripal and his daughter Yulia.

But Johnson went a step further and blamed Putin directly on Friday. He said “our quarrel is with Putin’s Kremlin, and with his decision, and we think it overwhelmingly likely that it was his decision to direct the use of a nerve agent on the streets of the U.K., on the streets of Europe, for the first time since the Second World War.”

Not only does that seem rather obvious, given the clandestine nature of the weapon involved, it seems to have been the point. Skripal had betrayed his country and his intelligence service, and Putin himself had publicly warned of the consequences for doing so at the time of his swap. Using a nerve agent like Novichok in a public place in a Western nation is a deliberate message that tells all those looking to dissent or to cooperate with foreign governments: We will find you and get you eventually.

Still, Jeremy Corbyn blasted May and Johnson for starting a new Cold War without conclusive evidence:

Jeremy Corbyn has defied critics in his own party and warned the prime minister against “rushing way ahead of the evidence” over the Salisbury poisoning, in what he called the “fevered” atmosphere of Westminster.

The Labour leader used an article in the Guardian to urge the government to take a “calm, measured” approach – and warn against the drift towards a “new cold war” with Russia. …

“This horrific event demands first of all the most thorough and painstaking criminal investigation, conducted by our police and security services,” he said.

“To rush way ahead of the evidence being gathered by the police, in a fevered parliamentary atmosphere, serves neither justice nor our national security.”

That ignores the opportunity that May gave Putin and his ambassador to explain how a secret Russian nerve agent — which is still undeclared, in violation of international treaties — wound up in a Salisbury restaurant. Putin had the opportunity to disclose whether it had been manufactured elsewhere, or stolen from a Russian government laboratory, or used by an agent gone rogue. Instead, they refused to respond. It seems that Corbyn is more interested in presenting a defense than Putin is.

Putin’s more interested in being on offense anyway. Sergei Lavrov announced that Russia will expel British diplomats in response to May’s actions, as expected:

Russia will expel British diplomats in a worsening global standoff over a nerve agent attack on an ex-spy — but still isn’t saying when or how many.

Russian Foreign Minister Sergey Lavrov on Friday also accused Britain of violating international law and said Britain’s defense minister “lacks education.” …

Lavrov said Friday that Russia will “of course” expel British diplomats and that he hopes the Skripals recover soon so light can be shed on what happened.

Yeah, suuuuuuuure. It seems unlikely that the Skripals will recover, and even if they do, they may not be able to recall what happened. And if they do, will they want to speak up again publicly after this attack? Not bloody likely — which is, again, the reason for the attack itself.

Lavrov’s deputy announced this morning that the Russians will also retaliate against the US for the sanctions announced yesterday:

Russia will expand its own “blacklist” of Americans in response to new US sanctions announced by the Trump administration, a Russian minister said Friday. …

Russia will use “the principle of parity” as it responds, Russian Deputy Foreign Minister Sergei Ryabkov said Friday, as quoted by state news agency RIA Novosti. Additional measures are not ruled out, he added.

Ryabkov tried to temper that with some friendlier rhetoric:

Ryabkov appeared slightly to soften the blow by adding that Russia did not want to close the window of dialogue with the US or the possibility of stabilizing bilateral relations.

“It is also worth thinking about that, destroying Russian-American relations,” said Ryabkov. “These politicians play with fire, because they simultaneously undermine global stability.”

Conducting disruption campaigns against Western elections and using nerve agents to assassinate people in Western nations has a tendency to do that, too, as does invading Ukraine and seizing Crimea. But hey, YMMV.