The killing of nuclear scientist Mostafa Ahmadi Roshan Wednesday joins a series of assassinations that left five Iranian scientists and experts dead in the past two years. These were central “knowledge bases” in the Islamic republic’s military nuclear program and their assassination disrupted the quest for an Iranian bomb.

Uranium enrichment is the largest vital component in Iran’s program and therefore also the most vulnerable to a military strike. For that reason, Tehran recently started to operate a new, well-fortified underground enrichment facility in a Revolutionary Guards base near the city of Qom. We can assume that Professor Roshan was intimately involved in establishing the new enrichment site. Hence, his elimination will disrupt Iran’s plans and undermine the timetable of the entire nuke project.

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eliminated . Four of them were scientists and one, Brigadier General Hassan Moghaddamm , headed the ballistic missiles project and was apparently an expert in the field. We can assume that many more lower-ranked missile experts were killed in several explosions in recent years at various Iranian sites.

The assassination of Iranian experts is meant to deter other scientists, including foreign ones, from getting involved in such projects. The eliminations also slow down these projects and force Tehran to reorganize. Moreover, killing key figures in vital projects greatly embarrasses the Iranian regime and security forces. Such operations portray the establishment as an incompetent bunch that time after time fails in safeguarding vital interests.

Mossad fingerprints?

The most important aspect of the assassinations is the killing of people who constitute “knowledge bases.” It is clear that any military strike on Iran would only thwart the nuclear and missile projects by a few years, but the elimination of key figures may extend the programs’ recovery period, if and when they’re attacked.

All indications show that a state organ is behind the assassinations. Only a state has the resources required to carry out the kind of operations executed in Iran . This includes investment in intelligence gathering that identifies the targets and prioritizes them, the investment of time and sophisticated means in preparing an operation against people or locations that are usually under heavy guard, as well as the recruitment and training of the perpetrators. National spy agencies are virtually the only ones that possess such capabilities.

For these reasons, the Iranians and the international media tend to point to the CIA or Israel’ s Mossad as the parties responsible for the assassinations and blasts in Iran. However, official American and Israeli spokespeople have not claimed responsibility for such operations.

According to the Iranians and global media outlets, the method of assassinating the scientists is reminiscent of the modus operandi utilized by Mossad in targeting top Palestinian terrorists in the past 30 years. The Iranians claim that Mossad’s fingerprints are evident in two aspects at least: First, the strict focus on the elimination target, while avoiding as much as is possible collateral damage and civilian casualties. Second, the utilization of motorcycles and masked assassins, thereby hiding the killers’ faces and making the getaway easy even on crowded streets.

In a recent investigative report by the New York Times, Western intelligence experts said there is clear evidence that the blasts at Iranian sites and the elimination of Iranian experts are securing their objective. We can already see a slowdown in the pace of the projects and damage to “assets” that the Iranians have already accumulated.

Iran’s silence

The most curious question in the face of these incidents is why Iran, which does not shy away from threatening the world with closure of the Hormuz Straits, has failed to retaliate for the painful blows to its nuclear and missile program? After all, the Revolutionary Guards have a special arm, Quds, whose aim (among others) is to carry out terror attacks and secret assassinations against enemies of the regime overseas.

Moreover, if the Iranians do not wish to directly target Western or Israeli interests, they can prompt their agents, that is, Hezbollah Islamic Jihad and other groups, to do the job. In the past, Iran did not shy away from carrying out terror attacks in Europe (in Paris and Berlin) and in South America (in Buenos Aires,) so why is it showing restraint now?

The reason is apparently Iran’s fear of Western retaliation. Any terror attack against Israel or another Western target – whether it is carried out directly by the Quds force or by Hezbollah – may prompt a Western response. Under such circumstances, Israel or a Western coalition (or both) will have an excellent pretext to strike and destroy Iran’s nuclear and missile sites.

Moreover, Tehran fears that Israel will take advantage of an Iranian attack in order to strike the immense missile and rocket arsenals funded or built by Iran in Syria, Lebanon and Gaza. The main aim of these arsenals is to serve as Iranian deterrence against a military strike.

Hence, it is no wonder that Iran does not wish to jeopardize these strategic assets only to satisfy its hunger for revenge and restore the regime’s prestige. This is also the reason why the Iranians made sure in recent years that Hezbollah would not fire rockets at Israel, carry out attacks in Israeli territory, or avenge the assassination of the group’s military commander, Imad Mugniyah.

Khamenei and Ahmadinejad are apparently showing restraint and sustaining the assassinations and explosions with clenched teeth, while ensuring that Bashar Assad and Hassan Nasrallah do not act foolishly, so that the retaliatory means remain intact and are available once the major confrontation takes place.