One of Rome's frequently asserted claims is to be "the church Christ founded." There are a lot of ways to handle that claim. One way to handle it is to ask, "Would the church Christ founded do what Rome did in Ireland?" (see the Wikileak-enhanced story here).
I realize some will simply say, "Yes - there's no promise that the Church will be morally perfect." But then again, there's no promise that the Church will always get its doctrines right - or even that it will always be politically one.
In fact the use of "churches" to describe Christianity was already prevalent in the apostolic period. The visible church is the sum of all those churches, but the apostles founded churches, and wrote to them (see Paul's letters or the book of Revelation for examples).
Does the systematic abuse of children, the coordinated coverup, and the protection and support of the abusers in and of itself prove that Rome is a false church? Of course not - it's just evidence that is hard to reconcile with Rome's grandiose claims for itself.