Taqiya is far more prevalent than might be imagined, and anyone dealing with Muslims must understand it, or he really can't deal with them.
Muslims have different standards of right and wrong when dealing with those in their own faith vs those who are not. This goes across the board, including business, outright lying such as taqiya, also sexual and romantic behavior.
IMHO it's more important and useful to raise awareness of these things than focus on the straw man argument posed here of "All / Some Muslims are Terrorsts."