Europe was key on the world stage at the time both in terms of its economic importance and against the USSR/Communists. The USSR is long gone, Russia is not a strategic threat to the US, and Europe is waning.
The US have sought to "pivot" away from Europe since Obama.
On the other hand, this would also probably reduce US influence in Europe.
I think you are wrong there. The USSR wasn't a strategic threat to the US in that there was a danger of them sending tanks to New York, it was a threat in taking over countries the US wanted to get on with like Vietnam and Korea. Russia is still merrily attacking or taking over countries that the US would rather it didn't.
At best it is a regional annoyance but at the same time the war in Ukraine has worked out very well for the US so far.
China is the main, and really only, strategic threat. Hence pivot to Pacific, which is also a much more dynamic area economically. Hence perhaps also attempt to build better relations with Russia as otherwise they are pretty much completely aligned with China.
Dealing with China's trade surplus requires a coordinated response, a large component of which will require the EU's help to setup similar tariffs against China considering they are the second largest consumer market.
If Trump tries to go it alone against China with just tariffs, all it achieves is just a repeat of 2016 which is largely ineffectual. And the cards the US has is running out, right now China's consumer market is too weak to provide growth hence we can use access to consumer markets as leverage, but once they achieve "Dual Circulation" in enlarging their consumption, the US (and most of the world) likely will be acceding economic dominance against an onslaught of cheaper Chinese exports (both in low-end and high-tech) while their internal market makes them invulnurable to any retaliation.
Russia has been openly attacking the US, not by military means, but still. Do you really think the former presidents Obama and Biden would tell you that Russia isn't waging a war against the US?
Hearing on the Internet that the US needs, according to your assessment, an impotent Russia as ally to fight China does not make it so either. But I get it, it's a very popular claim in certain circles on the Internet right now. You can almost tell where it's coming from. You know from whom I've never heard such a fantastic idea? Actual defense experts.
https://news.ycombinator.com/item?id=43229027