FOR ALL the ducking and regrouping by GOP congressional leaders now purporting to favor gun controls, nothing they have rustled up would close a mega-caliber loophole through which millions of guns are bought with few questions asked. Need an AK-47? Just let your trigger finger do the walking: Punch up any number of web sites and the mix-or-match makings of an at-home arsenal are on sale. Like the classified ads in publications -- only in far greater numbers -- the on-line gun shows' displays of weapons at the ready cover the range: "pre-ban" AK-47s, pistols galore, "military firearms" and menacing stockpiles of "ammo and mags," all available with no embarrassing criminal background checks necessary.

These transactions are legal -- and still would be -- in the packages of proposals that Republicans are embracing. The unaddressed loophole currently exempts unlicensed individuals from having to conduct background checks on buyers. Federal law does prohibit any sales to convicted felons, wanted fugitives, people judged by courts to be mentally incompetent or who have been dishonorably discharged from the military, and those who have been convicted of domestic violence counts. But with no background-check requirement for secondhand guns sold and bought by individuals, why worry about federal law?

After all, as NRA Executive Vice President Wayne LaPierre Jr. said in a report by the Richmond Times-Dispatch on the gun loophole, these person-to-person deals are all part of "a long, time-honored tradition in this country." Besides, the NRA lobbyists always note, criminals will get guns anyway.

True, any law can be broken. Loopholes only make it easier; and the Internet marts merely make the purchasing more comfortable for young would-be shooters readying for action.

Sen. Charles Schumer of New York is sponsoring proposals that would require that all web sites specializing in gun sales be licensed with the Bureau of Alcohol, Tobacco and Firearms. His legislation also would make it illegal to post gun-sale ads that would allow buyer and seller to complete any transactions without involvement of a licensed dealer. At the very least, lawmakers who are serious about effective measures should support this.

The new stirrings of longtime congressional apologists for the NRA are welcome signs that public demands for clampdowns on the all-too-free flow of firearms in this country are beginning to be heard. But loophole-riddled proposals that don't even include limits on the number of handguns a buyer may scoop up at one time are grossly insufficient. The president and congressional leaders ought to be pressing for a far more effective move to curb the gunfire: a ban on the general marketing of concealable firearms. Is there any candidate for high office in the country willing even to suggest action along these lines?