1. Don’t trust him.
2. Suspect all his motives.
3. Don’t rely on Russian supplies of gas/oil/anything.
4. Defend our friends who include the Ukraine and the Baltic States.
5. Ignore notional spheres of influence, including anywhere in Eastern Europe which no longer forms part of the Russian Federation.
6. Remember Hitler in the 1930s.
It’s alright to offer a carrot but don’t let go of the stick.