[Al-Khwarizmi]

Not an economist either, but my impression is that the USA is no longer seen as a serious, reliable ally.

If you displease the USA economically you may get tariffs, but then, if you don't you may get tariffs too, because the President is tweeting in bad mood, or because America first, or whatever random reason. So why even bother?

Also note that Brexit has increased the cohesion of the rest of the EU. The UK government with their ludicrous attitude has managed to make all other EU countries agree, euroskeptic movements have been largely discredited by the utter chaos that is Brexit, and there's also the fact that the UK itself always acted as a roadblock vetoing integration policies, and a pro-USA influence in the EU. So lately I'm seeing more teamplay and mutual support between EU countries than ever, which makes them stronger.