Gun makers often design their weapons in ways that present no benefit for lawful users but that greatly assist criminals. They don't coordinate the issuance of serial numbers so that each gun can be identified with certainty. They stamp serial numbers in places where they can be effaced.

They reject police requests to groove barrels to uniquely mark each bullet fired by a particular gun.

They sell bullets that can pierce police armor.

They will not include trigger locks and other child-proofing devices as standard equipment.

They ignore new technology that would render guns inoperable by anyone except their approved purchaser.

Why? Why? And why?

U.S. gunmakers have never been required to answer these questions. But one Senate subcommittee chairman with subpoena powers could cast much needed light on an industry whose record makes the tobacco industry look a paragon of transparency and accountability in comparison.

There's a gun agenda that need not depend on politics and that will not snatch a single weapon from any owner, whether law-abiding or not. If Congress stalls on the president's ambitious legislative schemes, the president should fall back on this Plan B to publicize what guns really do to those who carry them -- and what gunmakers do to their customers.

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