No- this is not possible in any reasonable sense. The chances are so infinitesimal of this happening in our lifetimes in the US. With ever increasing cultural diversity and technology that allows for transparent communication and education.
The bigger threat, though extremely unlikely, is the US becoming more like communist Russia than Nazi Germany, where a militant atheism could gain power and prevent mitzvos if they have a even a tiny sliver of intellectual appeal, i.e. shechting will be banned because its painful to animals and a bris mila will be banned because the baby does not have a choice in the matter.