Psy on several occasions has "rapped" about killing American servicemen and women.
His raps have included lyrics such as
"Kill those f–king Yankees who have been torturing Iraqi captives
Kill those f–king Yankees who ordered them to torture
Kill their daughters, mothers, daughters-in-law and fathers
Kill them all slowly and painfully."
It is an abomination he would be allowed to perform in front of the Commander in Chief of the US Armed Forces during the holiday season after singing songs about killing Americans.