So, he has a 12 or so year old history. It was resolved. Are we supposed to get background checks disclosing our past sins before we get on an airplane? I can guarantee you the seats will be empty once we get the morality police involved.
I think he should have been deported. Another immigrant from the third world with no deep commitment to the United States who abuses our laws, abuses our citizens and gets away with it. Under Mao or Ho Chi Mihn he would have been executed for his crimes.
Personally, I think United = Karma.