Fifty-six foreign policy experts and former U.S. government officials signed a letter dated Friday calling for proactive U.S.-led steps against the government. It comes as Syrian citizens and activists plead for world powers to help stop the government’s bloody crackdown.

They include Karl Rove, the former Bush administration adviser; Paul Bremer, in charge of the U.S. occupation in Iraq after the 2003 invasion; R. James Woolsey, former CIA chief; Robert McFarlane, former Reagan national security adviser, and Dan Senor, a former Bremer adviser and spokesman for the Coalition Provisional Authority in Iraq.

The letter can be found on the Foreign Policy Initiative website.

“We believe that the United States cannot continue to defer its strategic and moral responsibilities in Syria to regional actors such as the Arab League or to wait for consent from the Assad regime’s protectors, Russia and China,” the letter said.