The election of Joe Biden leaves Boris Johnson facing a substantial diplomatic repair job. The two men have never met. Last December the president-elect described the prime minister as a “physical and emotional clone” of Donald Trump.
There are people around Mr Biden who remember bitterly how Mr Johnson once suggested President Obama harboured anti-British sentiment because of his part-Kenyan ancestry.
Mr Biden and his team think Brexit is an historic mistake. They would not want Britain to leave the EU without a trade deal, particularly if it involved breaking commitments made in the Northern Ireland protocol.
Last month Mr Biden warned publicly in a tweet that a future UK-US trade deal was contingent on the UK not unravelling the Good Friday Agreement that brought peace to Northern Ireland.
There is an expectation among many observers that when President Biden seeks to repair transatlantic relationships, he may focus more of his attention on Paris and Berlin than London.
And when Mr Biden does turn his attention to the UK, he may put pressure on Mr Johnson to repair its relations with the EU just when the prime minister wants to focus his “global Britain” foreign policy elsewhere, particularly in the Indo-Pacific.
So the government has a lot of work to do to in improving its relations with the incoming administration. That has not been made easier by a reluctance of Conservatives in recent years to meet Democrats when visiting Washington.