Seeing this silly tee-shirt and smiling at it, I can't help but think of it as a sign of the times.
The Titanic was sunk, in a vain attempt to win the Blue Riband for an Northern Irish company, Harland and Wolff, on her maiden voyage. She was proceeding without caution as was standard practise at the time, under the command of an Englishman who had had his share of maritime accidents. Captain Smith himself had declared that he could not "imagine any condition which would cause a ship to founder. Modern shipbuilding has gone beyond that."
Now I wonder who told him that? Was that a case of an Englishman being deceived by an Irishman? How unusual.
And if you are Irish you have no more right to be offended by this than I as an Englishman have to be offended by the tee shirt slogan.
Anyway, it all happened a long time ago when they were both British and we were nothing at all.