President Obama's decision to send in 50 Commandos to assist in the training of forces to fight Assad and ISIS, is reminiscent of 1950, when President Truman authorized sending 35 troops identified as a  Military Assistance Advisory Group Saigon or MAAGS into Vietnam.  The 35 soon escalated to 342 by 1954, and were joined by 350 more in June, 1956.  Now I'm not saying that this will occur, but Washington ought not make the same mistake. Remember, the military commanders come with special brains which prohibit thinking about decreasing the size of their command, be it 50 Commandos or 550,000 American soldiers as in Vietnam by 1966.
So the message is clear Mr. President. Do not let Putin's play, and it is a play, drag you into doing something that you have said "no" to in the past. If you are going to commit America to stopping ISIS, use President Clinton's approach to Srebenica against the Serbs. Bomb ISIS 24/7 until the barbarian threat is eliminated.

 I agree, this is not a nice solution, but ISIS has shown a total disregard for those who fail to follow its precepts and not only does ISIS disregard the norms of war, it also destroys the past, not unlike the burning of the books as done by the Chin dynasty in China and by Nazi Germany.
If Washington is going to take action, then take serious action.