The past weeks have not been reassuring for those who thought that Europe could navigate its tricky relationship with U.S. President Donald Trump.

Trump this week lashed out at German Chancellor Friedrich Merz over his criticism of the Iran war, calling him "totally ineffective." On Friday, the Pentagon said it would cut 5,000 of the 36,400 troops it has stationed in Germany, and increase tariffs on cars and trucks from the European Union, a move that will hit Germany hardest.

Trump has taken aim at British Prime Minister Keir Starmer in strikingly personal terms, saying that ?he is "not Winston Churchill," and threatening to impose a "big tariff" on imports from the United Kingdom.