"In the meantime, Putin knows that if he attacks without a clear provocation, or on the pretext of some artificially created incident, he stands to lose more than he gains. In addition to the obvious costs of war, such a move would bring back the currently eroded resolve of European countries to back up any U.S.-initiated sanctions on Russia, including bans on hydrocarbon exports, bond issuance and cross-border financial operations. With a new German government promising to pursue a much more activist foreign policy, Russia would find it impossible to avoid heavy economic punishment. Increasingly dependent on China, it would have no one else to turn to and would thus face a threat to its sovereignty. The only potential winner in such a situation would be the U.S., which would be able to weaken its adversary and strengthen its alliances. The U.S. would likely then step up its military presence in any part of Ukraine that Russia cannot win or hold, as well as in other neighboring countries — the worst possible outcome for Putin."

Putin Needs a Real Casus Belli to Invade Ukraine