This article in Time magazine has got it dead right:
As Moscow Advances, U.S. Allies Look Warily to Trump for Clarity
Putin is playing a chess game with his pawns and knights while distracting the West. He has no interest in ISIS, Syrian rebels, or the Crimean people but has his eyes on Europe. He wants to break the EU and NATO and he is achieving his goal.
Putin’s aims are the ports of Crimea and Syria with access to the Mediterranean and he is now focusing also on Montenegro. He has stimulated the rise of nationalism in the UK, and the USA and soon to follow will be France (Marine Le Pen has promised to leave NATO), the Netherlands, and Germany. Similarly, influencing Eastern European countries such as Hungary, Bulgaria, and other former Eastern Bloc “members”. He continues to test NATO resolve with forays into Estonia and Eastern Ukraine.