> What if the relations between US and EU sour to the point that US is cut off from EUV machines and the Europeans cut a deal with Russia and China instead

That will not happen. I am an American, I greatly dislike Trump, but fundamentally you have to understand that if Taiwan is a stable enough country to sell EUV machines to, America's money is good enough as well. There is just no chance the EU plays this card, even with NATO threatened as a whole - selling EUV to Russia and China would be actual industry suicide with no tangible benefits besides the scorched-earth policy.