President Trump has been famously reluctant to criticise Vladimir Putin.
Last night, at least at first glance, the US President appeared to come off the fence with a forceful condemnation of the Kremlin and strong backing for the Prime Minister’s response to the attempted murder of former spy Sergei Skripal.
The White House statement was clear-cut - or so it seemed.
The statement by the Press Secretary on the United Kingdom’s Decision to Expel Russian Diplomats read as follows:
Strong in attributing blame, for sure. But was it actually a little less that Britain hoped for, and ambiguous after all?
A couple of points make me question the strength of the president’s true support for Mrs May in her hour of diplomatic need.
Firstly, it was written as a White House statement from the "Press Secretary" - not specifically from the president. It was formal and strangely impersonal. It was surely written by the National Security Council team (with input from No 10); not by the Oval Office. Trump’s name is not in it. It doesn’t say, "President Trump is outraged..."
Secondly, it is striking that Trump has not taken to his favoured platform to express his anger. His Twitter account is Trump’s personal megaphone (with 49 million people at the receiving end). In the last few days he has tweeted about everything: tax cuts, school violence, the Marine Corps, trade with Australia. You name it. Everything, that is, except the first use of a nerve agent in Europe since World War Two.
Thirdly, the White House statement is - to state the obvious - just that. Words. A statement. Easy to write; easy to release late on a Wednesday night.
It is far less clear that President Trump will seek to punish Moscow in any meaningful way. And as my colleague Robert Peston has rightly made clear, the only British response that will have any impact in changing Russian behavior is a multilateral one. The Prime Minister needs a coalition of the willing. All she has so far is a coalition of vague solidarity.
So if Washington is not prepared to take serious measures then Mrs May is going to be left frustrated. Moscow’s retaliation is surely coming, and Britain’s great ally is there in rhetoric only.
One final observation: just over a year ago, Bill O’Reilly of Fox News asked Trump about claims that Putin is prepared to sanction the killing of his enemies. Without missing a beat, Trump’s response was this: "There are a lot of killers. We have a lot of killers. Well, you think our country is so innocent?"
I’m not convinced Trump is as outraged by the Salisbury attack as Britain thinks he should be. And that’s an astonishing thought as London and Moscow head towards their own bilateral Cold War.