If there were some way of taxing in the US, without heavy intrusion into religious policy, I don't think there would be a bar. The Supreme Court is very unclear about this area. I believe it might be allowed on its face, the actual wording of the legislation. It might be struck down as applied. The details would be important.
Neutral tax lies, applicable to all, regardless of religion or nonreligion should pass constutional muster. I've not had the chance to research this so no one should rely on my comments. Perhaps I will have the time during summer break.
Altho right wingers were outrageous by Supreme Court internet research and noting foreign law (not relying on it, merely noting it), I find the European example a great way to see exactly where we are unique. Americans can be arrogant and assume the world revolves around us but Western Europe has a tradition of religious freedom in the modern world. I assume the American example had an impact but I more likely believe that the drastic change came from internal politics and culture. My writing sample for legal employment is based on the Establishment Clause, often incorrectly termed separation for church and state. If any Europeans know where I can access the history of modern European law regarding relgious rights, I'd be appreciative.