I still find that a group of Islamic men praying in the terminal just prior to a flight is sufficient grounds for suspicion. If we Christians were blowing up abortion clinics as frequently as Islamic terrorists blow up planes, we'd probably get the same reaction for praying in front of a clinic.
I'm sensitive to this as I have had friends hassled in the terminal for praying with talis and tefillin.
Muslims (like Jews) have set times for certain prayers. If they find themselves in the airport terminal during that time then they're going to do their thing.
Here we have three types of religious discrimination; let's see if they're warranted.
In the case of the observant Jews, it wouldn't appear to be. If their unusual dress or behavior made them seem like Muslims, then law enforcement needs to be better educated about the profile they should be worried about. Of course, I don't have any details about these incidents, so I could be wrong.
In the case of the infamous imams, I believe it was warranted. They were publicly, explicitly praying to the god of Islam just prior to boarding an airplane - this just a few years after Muslim militants committed 9/11. If they had done nothing else, that would have been enough to question the men before they boarded. Their religion required them to pray out loud at that particular time? Their religion is also connected to terrorism, around the world. The majority that fears them is not at fault. Al-Qaeda is to blame. I admire people who have enough honest religious devotion to endure ridicule or misunderstanding, but they shouldn't blame us for the due fear and caution engendered by militants of their own religion.
I have myself protested and prayed in front of an abortion clinic, and the Cheif of Police was there in person to enforce tiny laws that he probably made up on the spot. (We were told our large, heavy signs couldn't touch the sidewalk OR the grass. Our arms got a little tired that day.) Now if Christianity or anti-abortion sentiment had the same correlation with violence that Islam does with terror, the police would have been justified in taking actual security precautions of some kind. But I doubt any such correlation could be shown. Anti-abortion violence is rare and limited, both in death toll and in scope. And world-wide Christianity has much less connection to it than world-wide Islam does with terror.