I don't see how a family of Irish Catholics in the middle of Offaly or Clare as a threat to any Protestants in England or Scotland, unless you are a Bin Laden type like Cromwell.
The Catholic church is the esteemed Head of the still socially backwards Latin American culture and its heir countries throughout the Americas.
Liberation Theory isn't endorsed by the Catholic Church.
Nothing in your post legitimizes killing people if they don’t become Catholic.
I don’t see how Catholics could justify killing Protestants in the same way you stated in reverse.