Although there is no real blasphemy some nations put people into prison or even execute people for what they think is blasphemy against their favourite God. Pakistan and a few other backward Islamic countries are notorious for their cruel use of blasphemy laws.  Blasphemy laws are also found in Christian nations. 
Even in the United States you can't rely on the First Amendment. In Pennsylvania a teen who simulated sex with a Jesus statue risked 2 years in youth custody for violating a law hardly anyone heard of.  See Bullying a kid for more! Other states may have similar laws, we don't know. Does the Pennsylvanian law violate the US Constitution? Unless someone is heroic enough to mess with a revered object and take the case right up to the Supreme Court with a possible 2 year prison sentence hanging over him/her we won't find out.
Advice to readers who want to "blaspheme" in ways that might break the law in their country:
Don't! Learning and improving rational arguments against Religion is more effective and, at least in western liberal democracies won't get you into trouble with the courts. 
- ↑ Pakistan's blasphemy laws
- ↑ Why Blasphemy Laws Are Actually Anti-Islamic I don't know enough to tell if these laws are or are not Islamic
- ↑ Blasphemy and Censorship in Christianity and Islam
- ↑ Teen Who “Desecrated” Jesus Statue Hit with 6-Month Ban from Social Media and 350 Hours of Community Service
- ↑ Not every nation that holds elections is a western democracy, In Indonesia for example Alexander Aan got into trouble for promoting atheism.