(WASHINGTON) -- U.S. officials had once thought there was little chance that terrorists could get their hands on many of the portable surface-to-air missiles that can bring down a commercial jet liner.
But now that calculation is out the window, with officials at a recent secret White House meeting reporting that thousands of them have gone missing in Libya.
"Matching up a terrorist with a shoulder-fired missile, that's our worst nightmare," said Sen. Barbara Boxer, D.-California, a member of the Senate's Commerce, Energy and Transportation Committee.
The nightmare has been made real with the discovery in Libya that an estimated 20,000 portable, heat-seeking missiles have gone missing from unguarded Army weapons warehouses, thanks to the U.S. and NATO-aided rebellion against Moammar Gadhafi.
The missiles, four- to six-feet long and Russian-made, can weigh just 55 pounds with launcher. They lock on to the heat generated by the engines of aircraft, can be fired from a vehicle or from a combatant's shoulder, and are accurate and deadly at a range of more than two miles.
Peter Bouckaert of Human Rights Watch first warned about the problem after a trip to Libya six months ago. He took pictures of pickup truckloads of the missiles being carted off during another trip just a few weeks ago.
"I myself could have removed several hundred if I wanted to, and people can literally drive up with pickup trucks or even 18 wheelers and take away whatever they want," said Bouckaert, HRW's emergencies director. "Every time I arrive at one of these weapons facilities, the first thing we notice going missing is the surface-to-air missiles."
The ease with which rebels and other unknown parties have snatched thousands of the missiles has raised alarms that the weapons could end up in the hands of al Qaeda, which is active in Libya.
"There certainly are dangerous groups operating in the region, and we're very concerned that some of these weapons could end up in the wrong hands," said Bouckaert.
"I think the probability of al Qaeda being able to smuggle some of the stinger-like missiles out of Libya is probably pretty high," said Richard Clarke, former White House counterterrorism advisor and now a consultant to ABC News.
Adding to the urgency is the fact that America's passenger jets, like those of most countries, are sitting ducks, despite years of warning about the missile threat. Since the 1970s, according to the U.S. State Department, more than 40 civilian planes around the world have been hit by surface-to-air missiles. In 2003, Iraqi insurgents hit a DHL cargo plane with a missile in Baghdad. Though on fire, the plane was able to land safely. Four years later, militants knocked a Russian-built cargo plane out of the sky over Somalia, killing all 11 crew members.
Now there are calls in Congress to give jets that fly overseas the same protection military aircraft have.
"I think we should ensure that the wide-bodied planes all have this protection," said Sen. Boxer, who first spoke to ABC News about the surface-to-air security threat in 2006. "And that's a little more than 500 of these planes."
According to Boxer, it would cost about a million dollars a plane for a system that has been installed and successfully tested over the last few years, directing a laser beam into the incoming missile.
"For us to sit idly by and not do anything when we could protect 2 billion passengers over the next 20 years [with] a relatively small amount of money [from] the Department of Defense, I think that's malfeasance," said Boxer. "I think that's wrong."
And it could be more practical than trying to round up all the missing Libyan missiles.
"Once these missiles walk away from these facilities, they're very difficult to get back, as the CIA realized in Afghanistan," said Bouckaert.
When the Afghan mujahideen were fighting the Soviets more than two decades ago, the CIA supplied the Afghans with 1,000 Stinger surface-to-air missiles, which had a devastating effect on Soviet military aircraft. After the Soviets had retreated, however, the CIA spent millions of dollars trying to buy back the remaining missiles from the Afghan fighters. According to Bouckaert, the CIA spent up to $100,000 apiece to reacquire the Stingers.
"In Libya we're talking about something on the order of 20,000 surface-to-air missiles," said Bouckaert. "This is one of the greatest stockpiles of these weapons that has ever gone on the loose."
Tommy Vietor, spokesman for the National Security Council, which advises President Obama, says that a State Department expert "is on the ground in Libya working with the [Transitional National Council]," the rebels' interim government, to develop a "control and destruction program" for the missiles. Vietor also said the administration has sent five specialists to help the TNC "secure, recover and destroy" weapons, including surface-to-air missiles.
Said Vietor, "Since the beginning of the crisis, we have been actively engaged with our allies and partners to support Libya's efforts to secure all conventional weapons stockpiles, including recover, control, and disposal of shoulder-fired anti-aircraft missiles." Given the sheer number that have gone missing, however, experts agree the danger from these missing missile systems is very real.
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