What one does manifests what one really believes, and the religion of most politicians appears to be that self-serving pragmatism, whatever will get hem elected.
While you see it is as virtuous for a politician to renounces his/her membership in a church that sees Rome as false, i would see that as wrong if done for political purposes, as well as wrong in itself in this case (though that does not mean the view of the pope being THE anti-Christ is right), and your request would be akin to us demanding that a Traditional Catholic recant his/her belief that outside formal submission to Rome then one cannot be saved.
It is wrong and it is self-serving. Bachmann is a big phony.
Sarah Palin is The Real Thing.