On Tuesday night, the Obama administration began signaling that it will call for Bashar al-Assad’s departure in Syria. CNN and other outlets reported that the White House would soon increase pressure on the Syrian government’s finances, and isolate a number of officials in the Assad regime.

It’s about time. With each passing day, Assad’s forces brutalize his population and the death toll rises. According to Ammar Abdulhamid, a prominent Syrian opposition figure, as of last week, the regime had murdered 2,675 people, including 158 children below the age of 14, and detained 16,000. Another 4,382 are missing. In addition, since protests began in March, there have been 28 documented cases of rape and 89 of death under torture. Thousands of refugees have fled for Turkey or Lebanon.

Yet to date, the United States and its Western allies have taken few meaningful measures to stop the violence. As a first symbolic action, the Obama administration could ensure that the Assad regime never acquires the ability to kill on a far greater scale, by cracking down on Assad’s clandestine nuclear weapons program.

Washington and its allies should slap travel bans on Syria’s nuclear scientists, starting with Ibrahim Othman, the director general of the country’s Atomic Energy Commission. In addition, they should subject that commission and its twin organization, the Syrian Scientific Research Council—the state entity in charge of the country’s WMD programs—to restrictions similar to those already imposed on their Iranian counterparts.

This week, the Obama administration sanctioned the financial institutions most likely involved in financing Syria’s nuclear procurement efforts, namely, the Commercial Bank of Syria, which the U.S. Department of Treasury already listed in 2007 for its connections to the sanctioned Iranian Bank Saderat. U.S. allies should follow suit, and add the bank to their lists of designated proliferators.

Unlike the nuclear programs in Iran and North Korea, Syria’s nuclear activities have gone largely unnoticed, apart from a brief moment in September 2007, when Israeli jets bombed a suspected nuclear site at Dair Alzour.

Syria claims the site was a non-nuclear military installation, though the International Atomic Energy Agency has since concluded otherwise. According to an IAEA report on May 24, “The destroyed building was very likely a nuclear reactor.”

Syria is a signatory to the Nuclear Non-Proliferation Treaty, under which it must report all its nuclear activities and permit regular IAEA inspections. Yet since September 2007, Syria has covered up its activities at Dair Alzour and at two other sites, Marj al Sultan and Masyaf, which the IAEA now also suspects are connected to the bombed installation.

As a result of Syria’s failure to disclose the reactor’s existence, the IAEA declared it in non-compliance of its NPT obligations, and referred it to the U.N. Security Council on June 9.

Syria could have followed Iran’s tortuous path of plausible deniability by claiming that its exposed nuclear installations were meant for peaceful civilian purposes. Instead, in spite of all evidence to the contrary, it continues to deny that Dair Alzour was a nuclear reactor at all.

According to the IAEA, the characteristics of the Dair Alzour site are “comparable to those for nuclear reactors of the type and power alleged, i.e. similar to the 25 MW gas-cooled graphite moderated reactor at Yongbyon in the DPRK.”

Diplomatic sources in Vienna confirm that hard evidence shows collusion between North Korean and Syrian scientists. North Korea does not provide its hard-earned expertise for free, and according to the sources, Iran may actually have provided funding for it.

In 2005, Mohsen Fakrizadeh, the shadowy Revolutionary Guards official in charge of Iran’s military nuclear program, visited Damascus, probably to finalize the terms of the agreement. Clearly, Iran has a stake in Syria’s nuclear program and a strong interest in the survival of the Assad regime. Rolling up Syria’s nuclear program could thus set back Iranian political ambitions throughout the region.

The United States and its allies can exert far more pressure than they have on Syria. They can enact sanctions in response to Syria’s non-compliance with international obligations associated with its nuclear program. And at Obama’s discretion, Washington and its allies could expand these sanctions to squeeze Syria’s government finances as a whole, making it harder and harder for Assad to cling to power.

Though the IAEA has already referred Syria to the U.N. Security Council, Russia and perhaps China may yet shield Assad from any action other than rhetorical reproach.

Nonetheless, the U.S. and its allies can begin by seeing to it that, at the very least, Syria’s nuclear scientists and their agencies can no longer roam the world freely completing their shopping lists.

Emanuele Ottolenghi is a senior fellow at the Foundation for Defense of Democracies and the author of the forthcoming Pasdaran: The Army of the Guardians of the Revolution (September 2011).

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