The price to stop a madman with nukes and drunk with power increases with time and appeasements. You may hope that sacrificing people and countries now to his insane desires will buy the rest of the world time, but in reality that time will be used in the dictator's favor since he is the one with a terrible purpose: getting to you.
The price to stop Putin in 2014 would've been a local war with NATO losses. The price to stop him now is to risk walking the nuclear line. The price to stop him in another 10 years will be guaranteed nuclear war.