China would grab that plane and send it to a military airfield and "disappear" every single person on board if they thought that Muslim terrorists had planned on hijacking it to do a 911 style attack on China.

Don't forget they had just suffered a fairly major attack at the hands of Muslim extremists, and may have had their own reasons to think that plane was about to be hijacked. It would also be fitting for them to rig the takeover in such a way as to not let the Jihadis know what happened, knowing that the Jihadis have inroads into other nation's intelligence communities. Only the Chinese could pull off a stunt like that without US help, and in my personal opinion, they got US help but are going to be quiet about it, very quiet. I don't buy how the NSA cannot track the locations of those phones or that plane.