In the aftermath of the Sept. 11 terrorist attacks, gun stores nationwide are reporting increases in gun and ammunition sales. This news is surprising, but understandable considering that the attacks have taken thousands of innocent lives, devastated innumerable families and created a new sense of vulnerability among the American people. It appears that owning a gun gives people a sense of security against terrorism.

While citizens have the right to buy guns, a better way to feel secure is to keep guns out of the hands of criminals or potential terrorists. There is an easy and safe way to do this: require criminal background checks on all firearms sales, including those at gun shows.

The gun-show loophole that allows criminals to buy guns exists because federal law does not require a background check for someone who buys a gun from a private or unlicensed seller at a gun show. Buyers can acquire guns in those transactions without answering questions or showing identification.

It is through this back door that criminals and terrorists are given remarkably easy and undetectable access to weapons. This access can be seen in recent increases in weapons-related arrests of non-citizens—some even linked to specific terrorist groups. Just last year, for example, a previously convicted felon and terrorist, Ali Boumelhem, went to a Michigan gun show and purchased assault weapons, shotguns, ammunition and flash suppressors that he intended to ship to the terrorist group Hezbollah. Fortunately, Boumelhem was already under FBI surveillance for suspected terrorism and was captured before he was able to ship the weapons.

In Florida, four people were convicted last year of smuggling guns and other weapons out of the state for the Provisional Irish Republican Army (IRA). One of the convicted IRA terrorists, Conor Claxton, testified in federal court that he had gone to South Florida to buy guns at gun shows and was shocked by the variety of weapons available at gun shows and through newspaper ads. And on Oct. 30, Muhammad Navid Asrar, a Pakistani, pleaded guilty in Texas to immigration charges and to illegal possession of ammunition. State authorities reported that in the last seven years that Asrar, an illegal immigrant with suspected links to al Qaeda’s terrorist network, had bought several weapons at gun shows, including a Sten submachine gun, a Ruger Mini-14 rifle, two pistols and a hunting rifle.

Without across-the-board background checks and a database of firearms sales, it is extremely difficult for law enforcement officials to trace the source of guns recovered in crimes. Police have to trace firearms through manufacturers, distributors and individual gun dealers in a difficult, time-consuming process. Even worse, once a retail dealer has sold the gun, it can be re-sold by the owner and any subsequent owner generally without any records being kept, causing a trail of evidence to go cold before the criminal or terrorist can be found.

Under the current Brady law, which has been in effect since 1994, gun buyers must undergo background checks when buying firearms from licensed dealers. According to the Brady Campaign to Prevent Gun Violence, this law has stopped nearly 700,000 criminals and others from purchasing firearms. Imagine how many more criminals and terrorists would be prevented if the background check requirement were extended to all firearms sales.

This legal loophole has to be closed immediately. We cannot allow firearms to be purchased without any background check or other record of purchase. The stakes are too high. While citizens should maintain the right to own guns, no firearms should carelessly be permitted to fall into the hands of terrorists or criminals.