From Professor Juan Cole’s Informed Comment blog:
The countries most eager to stop the Iranian program are Israel, the United States and Saudi Arabia. So they are the ones with motive.
The means, a sticky bomb, is commonly used by radical militias in Iraq.
The opportunity belonged to an Iranian who could move freely and had his papers in order. Of course, such a person could be recruited as an agent by almost any espionage organization. An MEK double agent inside the Iranian Revolutionary Guards Corps would be useful.
If you put this all together, you can come to a speculation. The circumstantial evidence would point to a member of the Mojahedin-e Khalq (MEK or People’s Jihadis) terrorist organization. The MEK is known to have been involved in espionage on the Iranian nuclear program, and it wants to overthrow the current government in favor of a Marxist-Islamic regime, working with Israeli intelligence. Mossad does targeted assassinations, as in Dubai. The MEK has a history of pulling off bombings in Iran. One, in 1981, killed over 80 members of the revolution’s political elite, including the prime minister. The MEK is based in part in Iraq and so could acquire sticky bombs easily. It is known to have an operational alliance with Israeli and American intelligence. And that this bombing occurred on an anniversary of a previous one also suggests a terrorist group for which the date is symbolic.
I underline that this conclusion is circumstantial and purely the result of an intellectual exercise, i.e., of speculation. I’m not making an accusation and have no proof of this conclusion. But it is more likely the solution to the mystery than that Thai ninjas or Argentine gauchos did the deed.
Journalist Richard Silverstein says he has a reliable Israeli source who affirms that the bombings are a joint production of Mossad and the MEK. But since his source in anonymous, it is hard for others to judge the solidness of this source.
Anyway, the scientists so far killed have not been proven in a court of law to have done anything wrong at all, and so they have been murdered in cold blood for political purposes, which is the definition of terrorism. Western leaders who accuse Iran of being the world’s major purveyor of terrorism (a stupid allegation) would have to, if they were honest and consistent, speak out against these grisly murders in Iran (which also killed innocent bystanders).
Read Professor Cole’s full post here.