Zalmay Khalilzad, former U.S. ambassador to Iraq and Afghanistan, said today the “decision has to be made” for the U.S. to arm the opposition in Syria, but cautioned that the weapons should be ones that wouldn’t be used against Israel if they fall into the wrong hands.

“That’s not us fighting. (The Syrian opposition is) fighting, they’re dying, and they should be given as much a chance as possible to do it,” Khalilzad told me, after a speech at the Conservative Political Action Conference, in which he harshly criticized the Obama administration for what he called a failed strategy to “appease and engage adversaries” in the Middle East.

While it’s critical for the U.S. to do what it can to influence the situation in Syria, the idea of arming the opposition is controversial. Not only is there concern about who the opposition actually is, and whether they’re a group the U.S. would want to help bring to power, there’s also a distinct possibility the weapons could fall into the wrong hands. Khalilzad said this could be addressed by limiting our material support to purely defensive weapons.

“We need to be careful about what kind of weapons we give in terms of our regional interest. And we wouldn’t want to give them things that could be useful against our friends and allies,” he said. “I would think more in defensive weapons would be very helpful. Like anti-tank weapons because (the Assad regime is) using tanks to mow people and bomb.”

Outside of arming the opposition, there are also other–albeit, less effective–steps the U.S. can take. Khalilzad proposed reaching out to Christians and Kurds in the region to persuade them to join up with the opposition. He also suggested working with the Iraqis to block Iran from using Iraq as a corridor to channel supplies and weapons to Assad.

But in the end, Khalilzad said, “The will and decision has to be made that we will give them weapons, because this is important and the outcome will be important.”