The driving force behind these lawsuits is frustration over the inability of the Federal government to pass laws that would protect the public from themselves, in the case of cigarettes, and from others, in the case of handguns. To make this point is not to render sympathy to the devil. The gun industry, through its agent the National Rifle Association, has been particularly effective in resisting sensible controls that might have shielded the manufacturers from negligence suits. That said, you have to wonder where this all ends. The business of America is business, to quote Henry Ford.
Commerce requires a stable legal framework within which to flourish.
If you don't believe me, look at Russia. If every State decided to go after every manufacturer of a product that might have caused harm to their citizens, the Courts would be mighty busy, indeed. Twinkies make people crazy. Television fosters violence in our kids. Pornography breeds sexual violence.