Don't put too much stock in that Iranian anti-nuclear fatwa

But this fatwa — or any fatwa — is not inscribed in stone, says Mehdi Khalaji of the Washington Institute on Near East Policy.

“Fatwa is changeable by nature and the Shia theology gives this freedom to be flexible and go for the most updated interpretation and circumstances,” Khalaji says.

Iran’s supreme leader understands, says Sahimi, that circumstances in the world are always changing and thus fatwas must face scrutiny.

“Once it is issued, it doesn’t imply that it can never be changed,” he says. “The conditions can change and therefore a new fatwa can be issued that would basically nullify the previous one regarding the same issue.”

There are other concepts in Shiite Islam — lying to protect the life of Muslims or expediency to guard the interests of the state — that Iranian leaders could cite to reverse a fatwa.