Happened to a friend of mine way back in 2005, a Canadian citizen of Indian descent. He had a valid TN visa and was working full time in the US, regularly cross

Happened to a friend of mine way back in 2005, a Canadian citizen of Indian descent. He had a valid TN visa and was working full time in the US, regularly crossing the border between Canada and the US to visit family. One day he was simply barred by a CBP agent, and furthermore, permanently banned from entering the US, so he can’t even take a Canadian flight that goes over US airspace. He had a house, car, and job in the US for years. Reason given? Because he had once flown to Syria for an Arabic language education. Keep in mind this was before any war was going on in Syria.