Via Ace, carve out 10 minutes for John Sexton’s news mosaic of what the CIA was really up to in Benghazi when the jihadis made their move. The two leading theories for months have been that the agency was either trying to round up surface-to-air missiles that had gone loose before Al Qaeda could use them against western airliners or, more relevant to the news this week, that the agency was shipping weapons to the Syrian rebels from its base in Libya — in violation of a UN arms embargo.

This isn’t an either/or proposition, says Sexton:

During the U.S. involvement in overthrowing Libyan dictator Muammar el-Qaddafi during 2011, the Obama administration became aware that shipments of weapons were making their way to Qaddafi’s troops, allowing them to resupply themselves and pose a greater threat to civilians. So in February the US and other allied nations including the UK and France pushed for a package of international sanctions which became UN Security Council resolution 1970…

But despite resolution 1970, the NY Times reported in April 2011 that shipments of arms were reaching the Libyan rebels from Qatar. Another in-depth story published in Dec. 2012 describes how the U.S. winked at these shipments despite concerns that some weapons were falling into the hands of extremists…

This pattern of winking at violations of the UN arms embargo of Libya was repeated after Qaddafi’s ouster. With the war in Libya at an end and the one in Syria ramping up, the direction of the arms pipeline simply reversed itself. Whereas weapons had been coming into Libya from Qatar, they now headed out of Libya back to Qatar and from there on to either Mali or to Syria by way of Turkey…

But in late 2011 the Unites States realized its revolution-on-the-cheap in Libya had a worrisome downside. Thousands of dangerous anti-aircraft weapons were loose in Libya, attracting militants who might wish to use them to commit terrorist acts against civilian air traffic. Something had to be done.

Because of the arms embargo against Libya, he argues, and because the White House hadn’t yet decided to arm the Syrian rebels with American weapons, the only way to keep anti-Assad forces well supplied was to do it quietly by sending them foreign weapons that were readily available. That explains why the CIA would choose Libya, of all places, to use as a weapons hub. At first blush, that seems insane: Once Qaddafi was gone, the only thing protecting the American effort there from the militiamen and jihadis roaming the Libya landscape was the weak new central government. You’re not going to use a place like that as your base unless you have a very good reason to do so. But there was a good reason — weapons were easy to come by and a dangerous environment like Benghazi guaranteed that international bodies like the UN and western media outlets wouldn’t be able to sniff around what the CIA was doing without effort. The agency could pursue its twins goals of taking MANPADs out of circulation in Libya so that jihadis couldn’t get hold of them and sending some along to Syria where they could be put to better purpose against Assad’s fleet of Russian helicopters.

Two points to ponder in that case, though. One: If Sexton’s right that the CIA “encouraged the creation of a multi-national arms pipeline, helped shop for weapons to fill it, [and] vetted the groups who would receive those weapons in Syria,” then Syria’s an even bigger U.S. cock-up than we thought. By every account I’ve read, the jihadis in Syria have spent the past year steadily gaining strength at the expense of the “moderate” rebels. Yet if Sexton’s correct, the carefully vetted “moderates” have been supplied all along by the U.S. and its Sunni allies, in part via the illicit Libyan pipeline. Surely the totality of western arms shipments to the rebels didn’t dry up after the Benghazi attack. In which case, if you were worried before that giving arms to the Free Syrian Army would fail to turn the rebel tide against jihadis and maybe even backfire by having those arms fall into jihadi hands, you should be really worried now. Based on the past year of experience, that’s exactly what’s happened — and yet here are John Kerry and his pal John McCain, making the case this week that what we really need to do is “empower” the moderates even further.

Two: But if Sexton’s right, how to explain the curiously thin security at the consulate in Benghazi and the apparent conspicuousness of the nearby CIA annex? Joshua Foust calls those, correctly, the key unanswered questions a year later:

The two CIA contractors who died defending the outpost were part of a rapid response team, which was inadequate. Both the CIA and Ambassador Stevens had placed their lives in the hands of an inadequate American response team and a local militia that simply melted away during the assault.

Perhaps out of deference to the dead, there are few who have raised the question of why Ambassador Stevens had such faith in this unreliable militia. In the months leading up the assault, despite growing violence in Benghazi, Stevens repeatedly refused offers by the U.S. military to place more American security forces nearby….

To take things a step further, the CIA’s heavy presence in Benghazi is probably also why security was so light. Stereotypes to the contrary, in many places CIA facilities have surprisingly light building security; they rely more on obscurity than imposing defenses to stay safely hidden. When that obscurity is blown, so, too is their best line of defense. So why was the CIA station’s location so well known in Benghazi? Was tradecraft there so lax that everyone nearby knew what it was? And if so, who thought that was a good idea?

You’ve got two options if you’re running a top-secret international weapons pipeline to two different rebel factions from a war-torn Islamic country. Either arm it to the teeth with trustworthy security professionals so that it can repel the inevitable jihadi attack, or do it so secretly that not even the locals know what’s going on. The White House chose door number three — doing it basically out in the open and with the locals themselves providing most of the “security.” Why? Is this gross negligence or is there something else going on?