Earlier quoted context omitted.
Or Indifference? IS never really threatened U.S. or Western interests, the Paris attacks were the first time they reached so far. They (along with the Syrian regime) have been butchering Syrians by the thousands. Btw, the Daesh captive was Nicolas Henin, and he's actively campaigning against airstrikes [1] as that's exactly playing into their sick plans. And he speaks that they're deluded enough to think they'll find…
Do literally all Muslims despise the IS? After thousands of Turkish football fans starting chanting "allahu akbar" during the minute of silence for the Paris attacks, I would not agree. Who are the Muslims that support the IS?
http://www.101greatgoals.com/blog/an-explanation-for-why-tur...
TL;DR: Cultural difference. In Turkey, the "moment of silence" is used to chant for those who died in the attacks. They were not saying "Allahu Akbar", they were saying “Şehitler ölmez, vatan bölünmez”.
Translation: “Martyrs, they do not die (they are immortal), homeland (land, our land) is indivisible." Those who die in the attacks are considered martyrs, not those responsible. "Homeland" in this instance would be considered France.
Coming to your final point, every Muslim I know whether they practice or not hates terrorists. Earlier (those in rural regions) they had been fed propaganda that these were freedom fighters who had been discredited as terrorists since they were seen as fighting western aggression and invaders. Once they were shown instances of Marines/U.S. Army helping out/rescuing civilians in war-torn countries their entire perception is overturned, first it's disbelief that they would help the civilians, and later they understand that they're just humans looking for a better world as well and had only been doing their duty, and that countries & civilians pay the price for their leaders' arrogance & sins.