President Barack Obama finally called on Syrian President Bashar al-Assad to step aside and imposed new economic sanctions on the Syrian government. Both are overdue.

The Obama administration should have taken those steps weeks ago, when it became clear that Assad was determined to kill as many of his own people as necessary to hang on to power. Hopefully, the administration’s support for regime change in Syria means that it will now lead a broad international effort to isolate and weaken Assad’s regime. Without such a coalition, and U.S. leadership of it, the slaughter in Syria will continue.

The new U.S. sanctions freeze Syrian government assets in the U.S., prohibit Americans from engaging in transactions with Assad’s regime, bar imports of Syrian oil into the U.S., and prevent Americans from operating or investing in Syria. Although symbolically important, these steps will probably have limited effect on Assad’s behavior or his ability to wage war against his own people. The Syrian government has few assets in the U.S., and cutting off American trade and investment will have a limited impact on the Syrian economy. According to a senior administration official, about 90 percent of Syria’s oil exports go to Europe.

To be effective, the sanctions will have to be replicated by the European Union, Turkey and other major trading partners with Syria. The European Union should act quickly to adopt them. Multilateral efforts to prevent Syria from selling its oil would be particularly effective. Petroleum accounts for up to a third of Syria’s exports, the revenue from which accrues directly to the regime.

An anti-Assad coalition will also have to include Arab countries to prevent Assad from depicting attacks on him as attacks on the Arab world. Putting together such a coalition, and keeping it moving in one direction will not be easy. Only the U.S. can do it.

So far, the Obama administration has tried to lower the U.S. profile on Syria, perhaps reflecting fear of who or what would come after Assad, or a naive hope that Syria’s dictator could be pressured into enacting democratic reforms. Assad’s brutality has now forced the U.S. to act. What Americans perceived as caution, the people of the Middle East saw as vacillation and a lack of commitment to Arab democracy. It is time for the U.S. to act boldly to change that perception.

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