It turns out that whatever assurance Boris Johnson was given was not worth the paper that it wasn't written on.
The Executive Order contains no such assurance, and, this side of being struck down in court, the Executive Order is the law.
No American newspaper put Theresa May's visit on the front page. Not one.
British influence in the United States is, and has always been, a complete fantasy, believed only by preening British politicians and by Lyndon LaRouche.
But there are other British politicians.
They have ploughed a lonely furrow over the last 25 years, opposing the wars of Bill Clinton, George Bush, Barack Obama and Donald Trump.
They have ploughed a lonely furrow over the last 20 years, opposing the wars of Tony Blair, Gordon Brown, David Cameron and Theresa May.
No one has been more consistently at that plough than the man who is now the Leader of the Labour Party.
His election and re-election have been among their successes, and there have been others besides.
The biggest demonstration in British history did not stop the war in Iraq, but technological change made possible the lobbying campaign, organised by the same individuals, that did lead to the Commons defeat of the Cameron Government over Syria.
The removal of Tony Blair from the Premiership over the bombing of Lebanon also had its roots in the work of the Stop the War Coalition.
I used to think that that had run its course. But it is now needed even more than it ever was.
Organised by the people who had opposed Clinton, Bush, Obama, Blair, Brown and Cameron, and addressed by Jeremy Corbyn, the great demonstration against Trump during his State Visit would be the largest in British history, and it would politicise an entire generation, changing Britain for at least 50 years.
Bring it on.