Russia always was and still is the military opponent. NATO prevented that Putin would take back:
- Latvia
- Lithuania
- Poland
- Czech republic
- Slovakia
- Hungary
- Romania
- Bulgaria
What happens with Ukraine shows what the intentions of Putin are: rebuild a Russian empire wiht a lot of slave countries to serve them. He was able to catch Crimea already, and Belarus is close to be annexed too.
A good strategist looks into the future before he makes his plan. Strategists look to the future, never to the past as the past cannot be changed anymore. The future can.