Comment by Ravus

One should not overlook the human/emotional aspect. Decision-makers are not immune from it.

Hegemony comes with a certain degree of humiliation. Socially, it means accepting that a foreign language being taught in elementary schools becomes synonym with intelligence and eloquence, or protecting a copyright/taxation regime that go against your interest, or accepting that manslaughters perpetuated by troops stationed in foreign military installation on your soil will go unpunished, and so on. There's always been creeping resentment towards the US in any given European nation.

However, resentment is not a concern when "adults are in the room", even if not explicitly in charge. Economic prosperity is great, no one wants to break a good deal. But now those safeguards are failing on the US side. There's suddenly room to rationalize any hostility.

Sure, the extent to which this is a factor vs rational analysis is arguable... but I don't find it mere coincidence that France is the nation spearheading this.