The Central Intelligence Agency’s (CIA) second-in-command, Michael Morell, says the Syrian civil war is now the greatest threat to U.S. national security, the Wall Street Journal reported Wednesday. The risk, says Morell, is that the Syrian government might collapse and the country would becomes al Qaeda’s new safe haven, supplanting Pakistan.

In such a scenario, the chemical weapons that the regime of Bashar Assad now possesses will fall into the hands of the Al Qaeda rebels.

“It’s not so much that al Qaeda has fallen as a threat,” but that the threat from Syria has escalated, he reportedly said.

Although the U.S. is preparing to arm the same Syrian rebels in the coming weeks, the WSJ says it is doing so “reluctantly.” Morell himself is “skeptical of current administration plans to arm the rebels,” according to other officials.

In an interview summing up his 33-year tenure at the agency on Friday, Morell put Iran second on the list of threats, followed by the global al Qaeda threat, North Korea, and cyberwarfare.

He said that Syria is headed toward the collapse of its central government, with foreign fighters flowing into Syria in large numbers to take up arms with al Qaeda-affiliated groups. The violence in Syria has the potential to spill over into Lebanon, Jordan and Iraq, he explained.

Regarding Iran, Morell said that “There is in essence today a Cold War going on in the Middle East between Iran and the moderate Sunni states and the West.”

Iran, he said, is a major challenge for the U.S. and will remain so for the next 20 to 25 years.