If you by "in the West" you mean domestic western terrorism... maybe. Still, in the US the FBI and other gov't agencies monitor those orgs because of the potential to escalate into an undesirable state.

If you mean middle eastern terrorism jumping over into the west, I think it's fair to say that if they could, they would strike, but the threat has been managed well with the security precautions in place, but that's not to say they aren't trying to overcome their shortcomings.