If you don't want to be called one, don't act like one.
Yes you can. If someone scream "Allahu Akbar" as they blow themselves up, you definitely have something to go on. If, however, there is report of a terrorit attack and nothing more, you cannot. This was a case similar to the former.
When is the last time it took a US president THREE FUCKING DAYS to condemn a terrorist attack on US soil?!
There is only one of those in your mirror.