If you’re Franco, and you lead a country that is culturally dominated by a state church, dealing with religious issues is relatively easy: you simply enforce the existing monopoly. Putin’s relationship with the Orthodox Church has some of the same characteristics. Mussolini made a deal with the Pope. But America has religious pluralism in its DNA. What would an American fascist government do?
Religious tests would be a key component of any American fascist regime, but it would have to allow for some diversity. In all likelihood, instead of creating a new state church, the regime would have to create a list of religious groups that it considered to be adequately respectable and obedient for the purpose of enforcing the test. New, unreliable churches and existing left-leaning organizations would be banned. Nevertheless, there would be some competition and some freedom of choice permitted, as in the Third Reich.
The most difficult question for the regime would revolve around the treatment of the Jews. Given that some Jewish groups are extremely conservative, but most are not, there would be some debate on this point. In the end, the intense antipathy felt by most reactionaries towards the Jews would probably prevail, so Judaism in its entirety would be banned.