I know Ireland, including Northern Ireland is a small space, but after hundreds of years of fighting it's time to put it to rest. Do whatever it takes, but get it over with.
The Northern Ireland Protestants don't want to join Catholic Ireland. (Which is ironic as the Irish Republican movement was founded by protestants.)
The IRA is a bunch of communists trying to take over all of Ireland and using nationalism as a cover for their criminal endeavors.
Ireland is about as big as NY State if that, they can't really get away from each other if that's what they wanted to do. So unfortunately it's going to make finding peace a lot more difficult. As far as American Catholics sending money to the cause over there- I support a free, united and independent Ireland. But putting bombs in garbage cans and blowing up women and children is not the way to go about it. I would never send my money to any organization who does that. In my opinion, I'm not an expert on the Irish situation, but the IRA is discredited and should be treated as such.