And the Federal Government has the right to and sometimes the duty to pass such laws within the bounds of Federal Districts -- or better, that it delegate to the local governing bodies in such districts the authority to pass such laws.
I'd advise against regulating blasphemy -- but it is allowed and sometimes needed to do to restore proper social function. Does it regard religion? No. It regards harrasment of those have high religious standards.
Freedom of speech is crucial to Liberty and growth, yet stops short of harassment, and may and property should be restrained -- discretely and with the minimum force of police action imposed -- to break fads of social harassment, or stalking types of behaviour.
For example, to give one, say if some homosexual super-activists decided to stand outside of St. Pat's in NYC protest Church Policy. Freedom of speech certainly allows them to do that. Yet should they loduly blaspheme the key religious tenents, in my opinion, that blaspheming rises to "fighting words", just by being blasphemy that can be heard DURING the core religious proceedings.
Conversely, to use an example I barely find palatable, yet use to make a point -- if some good Christians wished to harass a Witch Coven's Halloween meetings, and did so by provocative mockery of that religious proceeding while the witches were assembled as witches -- that also would rise to "fighting words", like that of the blasphemy.
If however the Chistians lined the way to the proceeding, yet kept some distance from the actual assembly -- I'd say that would be okay. My opinion.