A Syrian soldier manning a checkpoint near Damascus. (PHOTO: ELIZABETH ARROTT/VOA)

Last night, in a televised interview with Charlie Rose, President Obama made the case for arming anti-Assad forces in Syria. In part, Obama was responding to critics who claim the U.S. weapons, once released, will be hard to control.

Is that true? Scholars who study small arms proliferation have looked at the 2011 war in Libya as a guide and found evidence of illegal arms transfers and poor tracking of weapons. More than a year after the war ended, no overall accounting exists of the total amount of lethal material allies like France and Qatar imported to Libya.

The doesn't mean the same will be true in Syria. And the U.S., which has some of the world's most stringent weapons tracking rules, was not a key supplier of lethal material to Libyan rebels.

But the parallels worry scholars. In a series of interviews begun last year, several investigators who follow small arms transactions argued that weak international rules for tracking transfers make it nearly impossible to account for weapons sent to non-government actors—like rebel militias in Libya and, now, Syria.

The basic rule under the End User system is that a country seeking to buy weapons from a private arms manufacturer in a second country has to obtain permission from the manufacturer's home government.

The clearest case in Libya involved bullets. In July 2011, the height of the Libyan conflict, the Swiss government discovered that rifle bullets produced by Ammotec, a subsidiary of Swiss defense giant Ruag, had turned up in battlefield photographs taken near the Libyan port of Brega, a key front in the then-raging civil war.

Switzerland had terrible relations with Qaddafi. But Bern had not yet recognized the rebels as Libya’s new government, and was not sending arms to the rebels. So how had the Swiss bullets made their way to a Libyan front line?

After members of the Swiss parliament raised hackles, officials in Qatar, which often buys weapons from Switzerland, admitted to violating an arms sale agreement. Qatar had re-purposed Swiss bullets bought for Qatar’s own defense, and shipped them to the Libyan rebels for use in the civil war. After six months of sanctions Qatar apologized for the violation, and shipments of defense equipment resumed. The embargo had amounted to a slap on the wrist.

The rebels won the war. But the supply chain for weapons, and regulations for controlling their distribution, had failed. Nearly two years later, with Qatar among the biggest backers of Syria’s rebels, we’re still trying to compile a picture of how many of the emirate’s weapons—and foreign weapons, period—ended up in Libya in violation of their original terms of purchase, as in the case of the Swiss bullets.

“What happens to the weapons?” asked Nick Marsh, an investigator at Olso, Norway’s Initiative on Small Arms Transfers. This was in a phone interview with Pacific Standard after the Swiss case emerged. “You’ve got concern about renewed fighting in Libya, and there doesn’t seem to have been much concern at the time about actually giving it to a coherent and unified people who can actually control them.”

What rules do exist?

Like most countries, Qatar buys most of its weapons under a loose set of regulations collectively called the End User framework. The basic rule under the End User system is that a country seeking to buy weapons from a private arms manufacturer in another country has to obtain permission from the manufacturer's home government.

“The country that has the ammunition or the weapons has to submit a formal request to the government of the producer of these weapons,” said Riad Kahwaji, director of the Institute for Near East and Gulf Military Analysis, a Dubai think tank.

Here’s the wrinkle: to get that permission, the government that wants to buy weapons has to promise not to re-sell them, or give them to a third party. The buyer has to assure the seller's home government that it will keep the weapons in its own arsenal: the “end user.”

That was the agreement Qatar broke when it moved the Swiss bullets from its own defense stores to the Libyan rebels.

The problem is, no international body is watching those transactions. The only interests in a position to know about an end user violation, said Marsh, are the country whose company sold the weapons, and the country that bought them. In many cases—such as arming a rebel force that both governments support—neither has much of an incentive to blow the whistle.

“To become public, the countries concerned have to come forward,” Kahwaji, the Dubai analyst, said. Though Qatar violated its “end user” agreement with Switzerland, the case only became public because a few Swiss politicians complained. That's not common. “This is the only one we have evidence of,” said Kahwaji in a phone conversation during the Swiss case.

Failing official channels to learn of violation, the only other option is to go find the weapons in the field. That means going to war zones, in this case Syria, and looking at serial numbers on the bombs and guns. The Swiss bullets had only been noticed by luck—some boxes with a brand name that showed up in a press photo. To really follow the trail would mean identifying specific weapons, then chasing down their serial numbers one at a time, painstakingly matching them against arms sales records from as long ago as the 1970s.

Some have done so, Marsh said. But even then it’s hard to determine when an arms sale is legal. He cites the case of a French anti-tank rocket called a Milan, which France supplied rebels in Libya. The French backed the rebels legally. But the Milan rocket isn't entirely French.

“Germany was opposed to the arms supplies [to Libya]," Marsh said. "And if you go back to the Milan missiles, those are made with German components.”

On one hand, the transfer of the Milans complied with the French government’s decision to send weapons to the rebels. On the other, Germany had no such agreement, and German material essential to the rocket’s operation ended up in the Libyan desert. Did Germany break its own laws, or not? Marsh couldn't decide.

A separate finding by researchers at South Africa’s Institute for Security Studies, released during the Libyan war's later stages, claimed that a South African armored personnel carrier called a Ratel had been sighted in Libya bearing a Qatari flag. “It is unclear how such a vehicle got into the hands of the rebels, as the South African government has not publicly reported the export of such military vehicles to Qatar,” wrote ISS. To date, ISS’ researchers have never determined the vehicle's source, or decoded a widely-circulated video showing the vehicle amid fighting. An entire tank, perhaps from South Africa, perhaps Qatari, perhaps never even in Libya, remains a ghost.

Nic Jenzen-Jones, a security consultant in Perth, Australia, spent much of the last two years trying to assemble an online catalog of weapons that turned up during the Libyan war, and now the Syrian conflict. He simply asked people to send him photos of weapons in Libya via a post on his blog. Pictures keep flooding in.

But confirmation is tough, and the quantity of material hard to determine from individual examples.

The Swiss bullets, Jenzen-Jones knew, were for a Cold War-era rifle called the FN-FAL. FALs were a common sight in rebel hands during the war.

How many FALs did European allies send to the rebels? A year after the conflict, no one knew. And still no one knows. To reconstruct how many FALs were already inside Libya before hostilities began, and which had come as part of international weapons aid, requires access to several governments' munitions data—good luck with that—or painstakingly cobbling together eyewitness accounts, most of which are unreliable.

“Most [FALS] are Belgian-produced, including a few less common variants,” wrote Jenzen-Jones via email. He’d posted his findings online, but at first was not sure how to see patterns in the menagerie of lethal material he was assembling. “I’ve also stumbled across a number of other oddities from Russian pump-action grenade launchers, to Romanian anti-aircraft guns, to Soviet flamethrowers,” he said. Some of that material certainly was looted from Qaddafi’s own stores at the time, as rebels overran government positions and took what they could, he said. The Syrians have armed themselves the same way.

But some likely came from across borders, said Jenzen-Jones. Which ones? In what quantities? No one knows, still.