Biff was based upon Donald Trump before he got into politics. So, you're right both ways.
https://www.rollingstone.com/politics/politics-news/back-to-the-future-writer-biff-is-donald-trump-190408/
Probably best for Ukraine and Europe were Trump to lose interest. Cut the US out of everything seems a sensible approach to almost anything at the moment. Let the adults work things out.
Only China and the EU are large enough to stand up to him. If they cooperate even better. Canada, although small, have some leverage due to the energy supply they provide to the US.