Inspired by the success states had against Big Tobacco, New Orleans, Chicago and other cities are readying liability lawsuits against the handgun industry. A new federal court decision, however, suggests that Big Firearms will be a more elusive target.

The Brooklyn, N.Y., case seeks to hold gun manufacturers and wholesalers liable for seven shootings with illegally obtained handguns; the victims claim the defendants negligently “oversupply” certain markets, thus increasing the likelihood that guns will end up in criminal hands. The claim took a hit Tuesday when Judge Jack Weinstein dropped wholesalers from the suit, saying the plaintiffs had failed to show a link between each of the 15 named wholesalers and the specific shootings.

And if the wholesalers, the next-to-last link in the connection between the assembly line and the street, aren’t responsible for guns ending up in the wrong hands, how can those further removed from the tragedies be held liable?

As the states did with tobacco, cities are going for the deepest available pockets. Although violent crime, including murder rates, are dropping, the numbers are still shocking — some 24,000 gun deaths per year, including about 500 children accidentally killed by playmates — and public outrage is high. Add to that the states’s $206 billion settlement with the tobacco industry, plus the numerous successful liability suits against negligent gun owners and retail dealers, and the temptation had to be overwhelming.

But the similarities between shooting and smoking don’t run particularly deep. Tobacco, when used as the manufacturer intends, is harmful. Firearms, when used as intended, result in sport or self-protection. Big Tobacco lied about the effects of its product. Firearms manufacturers sponsor safety programs. While there have been a few successful defective-product cases brought against manufacturers, those judgments have been for specific firearms that failed to perform as designed.

The Brooklyn case, which inspired the larger cases, is based upon two assertions: that gun manufacturers and wholesalers concentrate advertising in high-crime areas to increase demand; and that they flood jurisdictions that have lax gun laws with product that overflows into the more restrictive places. Gun manufacturers and wholesalers don’t control the circulation of gun-oriented magazines, the primary venue for advertising, nor do they write write the state and local laws regarding gun ownership. Both arguments are a stretch logically and virtually impossible to prove.

Probably the best the cities can hope for in their litigation is a concession by manufacturers to develop more fool-proof safety devices and to equip every gun with a trigger lock. Those measures would help prevent accidental shootings but, of course, would leave untouched the larger problem of crime. It’s understandable that cities would like a quick and sure way to get to those who use guns to commit crime and who sell guns illegally. It’s just unlikely they’ll find a shortcut through the civil courts.