What defines a Syrian rebel?

Today, the Washington Post reports that CIA weapons are reaching the opposition in Syria. Several rebel groups disputed the report. Whether the U.S. attacks Syria or deploys U.N. weapons inspectors, both policies risk deeper involvement in Syria’s civil war—and deeper engagement with Syria’s rebels.

But who are the rebels? That question is often neglected in this debate. There is no single opposition army as Secretary of Defense Pannetta told Congress last year: “It is not clear what constitutes the Syrian armed opposition—there has been no single unifying military alternative that can be recognized, appointed, or contacted.”

Instead, there are about 100,000 according to the State Department.

There is the Syrian Opposition Coalition, which loosely coordinates more than 70 rebel groups. The US—and several other countries—have recognized it as the political representative of the Syrian people instead of Assad.

Linked to that Coalition, there is the Supreme Joint Military Command, with representatives from many armed rebel factions.

It is supposed to help coordination—but its authority is based only on the military power of its members. So, unlike a civilian government, it has no independent legitimacy.

Then there are the individual rebel groups.

The largest is the Free Syrian Army, with reportedly 50,000 fighters. This is the group the CIA says it is arming.

It is led by General Salim Idris who defected from Assad’s Army just last year.

The Free Syrian Army is not actually an “army,” though.

It is a loose network of hundreds of units—some secular, some extreme. Analysts say the extremists are seizing more power—more on that in a minute.

Then there is the Syrian Islamic Liberation Front, which has more than ten thousand fighters, according to the Center for American Progress.

It is something of an alternative to the Free Syrian Army—it is more nationalist and more dependent on other states in the region, including Saudi Arabia.

Beyond these networks, there are also terrorists fighting Assad.

The US previously designated the Al-Nusra Front, Islamic State of Iraq, and the Levant as terrorist groups, as Vladamir Putin noted in his op-ed.

Al Qaeda funds Al Nusra, which practices suicide attacks. U.S. Government analysis have previously stated that Al Qaeda is trying to “hijack” the Syrian rebellion through Al Nusra. You can see a preview of what a victory by these groups would look like in Northern Syria.

Fighters have set up Sharia courts that hand out extreme Islamist punishments including beating Syrians for allowing women to remarry. And various rebel fighters have practiced torture and executions that violate international law, Assad is not the only lawless thug in this civil war.

This rundown is just a snapshot. But the nature of the varied Syrian opposition suggests three reasons we should be wary.

First, without an organized opposition that shares our values, it is hard for the US to responsibly take sides. If the enemy of your enemy is Al Qaeda, then the enemy of your enemy is still your enemy.

Second, there is no guarantee that this conflict will remain Assad versus everybody. There are literally hundreds of groups with different motivations!

They may be nominally aligned until Assad falls, but then without him, they could fight each other. That’s already happening. Last month, the Free Syrian Army reportedly fought Al Qaeda groups.

And finally, the hawks like to say our core fight is with violent Islamist extremists. Well, many of them are in the armed rebel forces!  We don’t want to help them.

How many rebels are fighting for a radical Islamist state—for a state that is more extreme than Assad’s regime?

We only have estimates, but they are high. A top military official told NBC that extreme Islamist groups constitute more than 50% of the rebel force—and it’s growing by the day.

So, who is the real enemy here? Something to think about after all the talk about international law, human rights, and defending our values.