Wonder if he realizes that in almost all of the colonies, Catholics and Jews weren't allowed to vote or hold public office. Yes. And, as I've mentioned, there were almost no Catholics or Jews in the earliest waves of English colonization. (Puritans in Massachussetts, Quakers in Pennsylvania, Protestants of various stripes in Maryland and Virginia, etc.) Later, especially 19th century, waves of immigration changed the mix.
I'm not going to mention how the whole line of argument about a lack of Catholic and other signers of the D of E strikes me, as I've mentioned it elsewhere. ;)
I have at least one Catholic ancestor whose service in the American Revolution entitles me to join the DAR. He lived in Point Coupee, Louisiana, and fought with Governor Galvez against the Brits. We learn about that campaign in Louisiana history, about the capture of forts Kaskaskia, Cahokia and Vincennes, but I don't think anybody else learns it.
http://www.thecajuns.com/galvezrw.htm