"Can't we risk (right word. I admit) showing how intelligent, tolerant, forgiving, and experienced Catholics behave and declare the relentless zealotry of the Catholic McCarthyism of Burke and others unacceptable in ourselves as well as in others?"

We can.  But if the "relentless zealotry" is ever going to stop, sooner or later someone is going to have to say "Have you no sense of decency, sir?  At long last, have you left no sense of decency?"