I don't have a dog in the fight here, but lel.. Are they trying to use the Catholicism bit to essentially do the same thing as muslims? Rally up the boys, deus vult, etc.? On examination, there appears to be a big difference between those that seek solidarity with the overhanging banner of brotherhood (race, in the case of alt-right people), and then those attempting to toss over a false label on top of things. There's probably a lot of people in your movement that have found faith this way, but it looks suspicious considering the rest of the behavior that doesn't really mesh with the religion.