The details of the story are developing, but this is the synopsis....
According to the American government, elements inside the Iranian regime were willing to pay Mexican drug dealers $1.5 Million (USD) to kill a Saudi official in the US, and possibly dozens of bystanders, potentially sparking a war that Tehran is ill-equipped to win, during a time of increased isolation in the world and the region for the Islamic Republic.
All the evidence that we currently have to evaluate this claim can be divided into two categories: the official US complaint against the alleged Iranian agent Manssor Arbabsiar, and common sense.
The common sense answer is that this is a preposterous story, Iran would have nothing to gain and everything to lose from this act.
The complaint says that the US Attorney General has detailed and elaborate documentation that explains allegations which, at this moment, are general and lack corroboration.
So far, analysts are either flocking to one of two poles: 1) a historical argument that Iran is a suspected state-sponsor of terrorism and an antagonistic member of the international community, so this fits the pattern v. 2) the geo-strategic explanation that this makes no sense in a calculated approach to towards the region and the US and so the claim must be false.
Both arguments are problematic because they miss two fundamental questions: 1) if this story is real, why would the Iranian regime want to kill this Ambassador?; 2) if this story is fake, who would benefit from framing Iran?
Then, there is the third possibility...
Both theories are correct. The Iranian regime, on the whole, would not benefit from this attack, but certain elements within it would benefit from the existence of conflict. In such a scenario, who stands to gain?
Let's first assume that this report is true, and the plot was authorised at the highest levels of the Iranian regime. All the consequences of such an attack would result in an overall loss of Iranian power. Tehran would alienate those who might ally with it over a "peaceful" approach to its affairs and those of other countries, as well as Sunni regimes in the Arab world, incur additional financial sanctions, and possibly reap the military whirlwind from a combination of of the US, Israel, Saudi Arabia, and a coalition from the rest of the Gulf Cooperation Council countries. Meanwhile, innocent civilians and one entirely-replaceable diplomat would be killed, as well as several non-military targets.
So why risk all this to kill the Saudi Ambassador to the US, Adel A. Al-Jubeir. Is there something that Al-Jubeir knows or is which he is involved that would give Iran a reason to kill him? That is a real-life James Bond plot, but if one is making the assumption that the Iranian regime really wanted this man dead, then it becomes an important question. Revenge for Saudi action in Bahrain is a pretty weak excuse to start a war that does not otherwise benefit Iran.
There must be more to the story.
Now Assumption 2: Iran was framed. The FBI and the Drug Enforcement Agency jeopardising their crime-solving reputations to engage in some geopolitical game...to do what exactly? The US is still involved in two wars in the region, and is in the middle of a heated debate on cutting spending, including military expenditure and foreign aid.
As for direct action against Iran, Washington has already --- through a visit from Secretary of Defense Leon Panetta to Israel last week --- ruled out military action against Iran. The US is close to maximum capacity on international sanctions, adding named individuals to the list of pressures applied to the regime. So why pursue such a bold deception for some incremental additions (three more members of the Quds Force of the Revolutionary Guards were cited yesterday)? And is really worth the risk to pull China and Russia closer to more --- unspecified --- political steps against Tehran?
The motivation for framing Iran is even more improbable than the motivation for the top levels of the Iranian regime wanting to carry out this attack.
This leaves the third assumption that some elements inside the regime, but not the Iranian regime as a whole, would benefit from this attack. The key to this approach is not to think about the attack's specifics, but the generalities --- who would benefit from renewed and intensified conflict between the US/Saudi Arabia/Israel and Iran?
Applying a broader lens to the region shows that the Iranian regime has been weakened by Arab Spring. Specifically the Iranian Revolutionary Guard Corps lost influence, and beyond Iran, the Lebanese organisation Hezbollah is losing its primary ally, Syria.
The greatest irony of Arab Spring is that the threat to Israel may no longer be terrorism but the potential for a unified pro-democracy movement. And the greatest threat to Iran might be the awakening of that movement inside its borders. If either of those scenarios occur, the Revolutionary Guards and Hezbollah perhaps have the most to lose. In contrast, amidst the reaction to an attack such as the assassination of a diplomat, the mobilisation of a militant opposition to the "West" would benefit both organizations, as they would call their supporters to action against a revived external threat.
The bottom line, though, is that there simply is not enough evidence for any of these three scenarios, and the speculation is getting in the way of the real questions.
Unless the US Justice Department faked this report, then 1) there are either unknown reasons why this event would benefit Iran or 2) there are serious fractures within the Iranian regime, presenting both a threat and an opportunity to those seeking peace and stability in the region. While the war hawks beat the war drum, and the sceptics cry fraud, and the Attorney General shines his badge, and the Revolutionary Guards thunder about the "enemy" US, the real story might be already slipping through the cracks.