Arguments based on generalizations or "no True Scotsman" fallacies are unhelpful and as here, somewhat demeaning. That a wide swath of the Left has always been anti-theist is very old, and hardly a new development. Should we hold our tongues and crawl under the covers just because our views may sometimes be congruent with militant atheists?

Have you forgotten that Jim Crow in the USA was first attacked by open Marxists before people of more moderate politics (and faith) took up the cause of civil rights? As to alliances with those who don't like you at all, consider the many evangelicals and biblical inerrancy and advocates of premillenialism who have toxix things to say of your church and the Papacy in general. Doesn't seem to faze folks like you. How come?