Most people in the field of terrorism will agree that the IRA is a terrorist movement.
Public perception is of a similar notion save for the Irish nationalists.
For this article, lets see how the United States fits the above category. The US courts on occasion have recognized that political persecution is a just claim for asylum. Not all judges accept this due to recent extradition of three Maze escapees. So the US government does allow a safe haven for terrorists in this sense. By allowing Gerry Adams to visit the White House and Senate officials it does bestow on Sinn Fein a form of diplomatic recognition.