So we should go back to having laws against blasphemy?
Yes.
Next question?
That would be forward, not back. Yes we should.
A technicality: under American constitution specifically "blasphemy" might be a problem because of the so-called Establishment Clause. Moreover, I find it awkward to consider insults of Mohammed blasphemous, -- he is no God. I would propose instead a broader system that removes free speech protection for speech merely designed to insult, demean, or encourage masturbation or violence.