I'd say war became hot again way back when with Vietnam, Afghanistan, and Korea. Proxy wars but wars nonetheless. A major war? Perhaps 2022 was the start of it like you said, that tracks. Hopefully not though.
1. Short term: nothing major because it can't at the moment.
2. Long term: build up a military that is a credible military deterrent to the US, probably abandon NATO if the US doesn't, and form alliances with Canada and the UK.