If you’re keeping score, freeing Islamic terrorists from Gitmo does not play into the hands of ISIS. Neither does bringing Syrians, many of whom sympathize with Islamic terrorists, into our country. And aiding the Muslim Brotherhood parent organization of ISIS does not play into the Islamic group’s hands.
However if you use the words “Islamic terrorism” or even milder derivatives such as “radical Islamic terrorism”, you are playing into the hands of ISIS. If you call for closer law enforcement scrutiny of Muslim areas before they turn into Molenbeek style no-go zones or suggest ending the stream of new immigrant recruits to ISIS in San Bernardino, Paris or Brussels, you are also playing into the hands of ISIS.