(CBS) The Bush administration dropped the federal terror alert level back to yellow from orange on Friday, saying intelligence pointing to an imminent attack has decreased. But CBS News has found a big hole in America's anti-terror security net.

While it may be causing heartburn for the rest of us, the heightened alerts have been a bonanza for the gun business, reports CBS News Correspondent Jim Stewart.

"When the higher level comes, we start seeing people come in and buying more guns. They're sacred," says gun dealer Don Davis.

What's scaring many lawmen, however, is just who may be buying those guns. Currently, phoned-in background checks only filter out convicted felons, fugitives and a handful of others before a sale is completed.

None of the names on the State Department's terrorist watch list or the no-fly list, for example, are on the background checklist. Even Adnan Shukrijuma, a suspected al Qaeda cell leader sought as a material witness by the FBI, would not show up in a background check by a gun store.

"Why on earth would we want to shield the terrorists from being identified?" says Sen. Frank Lautenberg, D-N.J.

Lautenberg has introduced a bill that would give lawmen more time to conduct background checks during heightened terrorist alerts, as well as restrict the amount of black powder that can be sold. Currently stores can sell up to 50 pounds with no background check required. And there's evidence Al Qaeda has taken notice.

"It was found in a manual, a training manual for al Qaeda in Afghanistan in which they suggest that you can find weapons in the United States cheap and they're easily available," Lautenberg says.

Many gun dealers and the National Rifle Association argue there are enough checks in place already. But Davis, for one, feels adding a few more wouldn't hurt sales

"My God, we do records all day. That one more record of checking out one more guy is certainly not going to make any difference if you love this country. And brother, I love this country," Davis says.

The problem is getting all the various agencies to agree how to consolidate their terrorist watch lists.

Until then, the scary reality is the FBI might want you, the airlines won't sell you any tickets, but you can still buy a gun in America.