The humiliations inflicted by Donald Trump on his allies, especially in Europe, since his return to the White House, meant that no one was saddened by his historic defeat in the midterm elections on November 3. That sense of satisfaction may, however, be short-lived.

Faced with a Democratic-controlled Congress determined to use its prerogatives, especially over the budget, the American president could well turn to a domain that falls almost exclusively within his authority – foreign policy. He has two years remaining to finish imprinting his influence on the diplomatic direction of the United States.

In 2006, after George W. Bush's administration lost the midterm elections due to growing public opposition to the invasion of Iraq, Secretary of Defense Donald Rumsfeld took responsibility and resigned. It remains to be seen whether his distant successor, Pete Hegseth, will do the same after the resounding vote against the Iranian adventure.

The late admission by Vice President JD Vance – undoubtedly with an eye on the 2028 presidential election – that the joint attack on Iran with Israel was a major error, and the fact that Israel's image also suffered at the polls, likely signals a search for a negotiated way out.

The president's team of personal advisers, which has proven its amateurism, is poorly equipped to achieve such an outcome. The "lame-duck session," the two months before the new Congress takes office on January 3, does not rule out a renewed outbreak of hostilities – even though voters repudiated them – in an attempt to improve Washington's position.

It is unlikely, however, that Trump will revise his position on relations with Europe, as he once again aligns himself with Russian stances on the conflict in Ukraine – a potential source of confrontation with the incoming Democratic majority in Congress. The reaffirmation of American influence in Latin America, made easier by the rightward shift of nearly every South American country except Brazil, is also likely to continue, as are efforts to undermine international justice and the already ailing institutions of multilateralism.

In all these areas, Washington is expected to keep prioritizing its national interests over those of others. There is no reason to believe that the US's aggressive trade policy will undergo any fundamental change as a result of the Democrat wave – even if Congress will no doubt try to ease tensions with neighboring Canada.

Europe must not hope for a restoration of a bygone era. The American "pivot" toward Asia was first announced by Trump's Democratic predecessor, Barack Obama. Every US administration has called for burden-sharing in the defense of Europe with its primary stakeholders – though the concept of sharing has now effectively been replaced by that of transfer.

Less acrimonious, more stable and predictable relations with Washington would be beneficial. But Europeans must remain convinced that they can now only rely on themselves, and that their unity is more essential than ever.