Russia's greatest weakness is their economy and its' dependence on the West. We need to ramp up the sanctions to include oil/gas, which much of their (weak) economy is based upon. Make them a pariah state. Get real news somehow (via satellite, 5G, internet - however) to the population to let them know the truth about Putin's regime. IOW, get his own people to take him out.

Russia's greatest strength is their military and nuclear power. It would be foolish to confront them directly, especially to invade their homeland which would be certain to trigger nuclear war.

If he ever attacks NATO territory (very unlikely IMO, he's a coward) then we would be compelled to defend the alliance, likely in a non-escalatory way, to prevent nuclear war.

Our biggest failure vis a vi Russia/Putin was a failure of imagination. He played us, by getting the gullible/corrupt/traitorous to buy into his victimhood narratives, which prevented us from being more forceful about admitting countries like Ukraine and Georgia into NATO. Putin tested us by gradually compromising the borders of neighboring countries. It was a test run for what he is doing now. He knew nobody would defend Ukraine and is taking advantage. He will never attack a NATO nation as he knows it likely would be the end of him.