I had some hassle singing "Take It Down From The Mast, Irish Traitor", a republican song that condemns the Free State. If you listen to the words, you will understand why it made some folks nervous. It was a favorite number among the Provisional IRA members.
Another incendiary song was the republican version of "Let Him Go, Let Him Tarry" Here's the first verse and chorus.

Jack Lynch come up from Dublin with his band of merry men.
He marched 'em up to the border, then, he marched them back again.
Ah, such an armored column, boys, the like you've never seen.
Five hundred mounted bicycles, all wearin' of the green.

Let him go, let him tarry. Let him sink or let him swim.
He don't give a damn for us so, why should we, for him.
He sits on his ass in Dublin and I hope he does enjoy
Selling out his country for he's England's little boy.