Vladimir Putin’s message of defiance to the US and its allies presents an immense challenge for Joe Biden.
President Biden’s administration had been signalling for a while that a decision by Mr Putin to recognise the regions of Donetsk and Luhansk as independent would necessitate a firm response.
The sanctions the White House announced in retaliation – targeted on new investment, trade and finance in those regions of Ukraine – may well be followed by additional measures, but they undoubtedly represent a limited first response.
The White House has made clear there is more up its sleeve should Russia “further invade Ukraine” in the form of “swift and severe” sanctions that it has promised would be unprecedented in scale and scope.
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The White House believed it had caught Mr Putin off-guard by providing a running commentary of what its intelligence was telling them.
But the belligerence revealed by Mr Putin now bears out the utter conviction felt in the White House since last week that he had decided to power ahead with confrontation with Ukraine and the West.
Officials resisted putting those sanctions in place before any invasion, despite the pleading of Ukraine’s own president, because they believe that will lose the deterrent effect. They know that Mr Putin largely already knows what those sanctions would contain but they evidently want to maintain some element of surprise.
And a breach of international law and the wholesale rejection of the Minsk agreements by Mr Putin, in the eyes of Washington, is hardly the action of a leader looking to lower the temperature.
Even before his announcement the White House had been sceptical of Mr Putin’s commitment to diplomacy. It was doubtful, to say the least, that any summit with Mr Biden would actually happen.
But listening to Mr Putin’s history lesson for the Russian people recalls that Washington has been invoking its own references from Russia’s past in recent weeks.
Officials openly questioned whether Moscow was engaged in “Potemkin diplomacy” – a reference to fake facades erected to hide the truth during the time of Catherine the Great – the process of saying one thing in public but doing the complete opposite.
Those suspicions seem to be justified.