I don't think this is the case in the long term.
1) Europe will rearm for sure and be fully aligned with the U.S.
2) Belt and Road is probably dead in Europe, hopefully they can salvage some of it but I don't see how.
3) Performance of Russia's conventional military hasn't been the best, it would degrade European and U.S. perception of their capabilities. Which would in turn lead to
4) U.S. will be able to focus more on the Indo-Pacific.
Comparison with 9/11 is not appropriate since Al-Queda and Taliba were NOT a part of the Chinese camp, but the Russians are.
I wanted to address your points in specifics briefly, and talk about the strategic picture, but it looks like everyone already beat me to it, lol.
To summarize briefly.
1. Europe will rearm, but they will use their limited budgets to buy tanks and not a navy. EU tanks will not drive through Russia to threaten China. The west will be on the same page probably regarding Russia. It remains to be seen if they will be unified with respects to China.
Just a hint of what may be the case, Bolsonaro of Brazil maintains a neutrality for this European war. The culture of South America is Spain and Portugal. Those two were neutral during World War Two.
2. BRI is not dead in Europe, BRI already there in Europe. They will not scrap existing projects. Will they do new projects? Time will tell. The key thing to watch here is the trade volume done with rail from China to Germany. If it increases, like it should, the BRI alive and well in Europe.
3. & 4. No matter what happens, everything leads back to China for the Americans. They have been saying that for a generation now. And all they have done is start a trade war and tech war, both of which they started but could not finish. All the CCP can really do, probably they will humour the Americans a little bit.
After the trade war, tech war, Russia Ukraine war, not sure what is left for the Americans to do.
9/11 was a big win for China because it distracted the Americans for a generation, which the Chinese took the time to build up, everything!
Russia invading Ukraine is a big win for China because now the west or whoever is still on the side of Team America, has to contend with the Russia-China partnership in three theaters.
Europe - they must counter the Russia-China in Europe with this war
Indo-Pacific - whatever the strategy is there,
globally - the west must compete with China globally for market share.
The trade war and tech war, has shown that the Americans are incapable of competing on an economic level with China in the Indo-Pacific and globally.
China's trade numbers keep going up, to be the biggest and more biggest trader in the world. Not sure what they mean when they say America will focus on China in the Indo-Pacific. Do they mean they will focus on China winning? I don't know.
Then the American now are in a very not envious position, of reiteration the security aspects for the Indo-Pacific. Security is important, like what we are seeing in Europe today!
Thanks, but no thanks.