Very surprised they even started such a stupid idea. NO to Shannon-US routes!
Look I know you're only 17 but I would have hoped you knew SOMETHING before opening your mouth. Shannon has it's own market, in the same way that EDI and GLA are both served by Continental, the difference being they don't fly EDI-GLA-US.
Aer Lingus cannot do this with the A330 as it's just a little on the big side to be operated from Shannon year round. Both markets are recognised and served seperately and Shannon seems to have enough traffic to have supported Aer Lingus and few US carriers, though fewer than in the days of the stopover.