All religions are belief systems, and we all have the inalienable right to believe whatever we want as long as it doesn't adversely affect other people. What I don’t consider we have the right to do is force those beliefs down other people’s throats.
Accordingly, I consider blasphemy laws to be one of the greatest evils known to humankind (and I use the term ‘evil’ in a general secular sense, not a religious one.) I deem them to be a means by which the despot maintains control over the blind faithful, and I further consider that those individuals or regimes who assume the right to arrest and punish blasphemers – often by killing them – should themselves be brought to trial on a charge of perpetrating crimes against humanity.
And, ironically, if I were a religious person I would consider the very concept of blasphemy to be the grossest insult to God, Jesus, Mohammad, the Buddha or any other spiritual figurehead. Such figureheads should surely be regarded as superior beings, so why would I deem it right to believe that such a figurehead could be sufficiently insecure as to be offended by the mere mutterings of an inferior species?