Those questions are at the center of the rapidly escalating tobacco war and the focus of events last week that marked new setbacks for the industry. Philip Morris went on the offensive with a big splash, filing a $10 billion libel suit against ABC News for reports that the industry “spikes” cigarettes with nicotine to keep smokers coming back. But new moves by other critics Will be harder to combat and may end up having greater impact than any prime-time TV slam. Food and Drug Administration head David Kessler testified in congressional hearings on whether the FDA should regulate cigarettes, and Labor Secretary Robert Reich proposed new rules virtually banning smoking in the workplace.

In its lawsuit, Philip Morris charged that ABC’s news magazine “Day one” falsely accused it and other companies of spiking some cigarettes with extra nicotine in order to keep smokers hooked. Philip Morris and R.J. Reynolds, which says it may also sue, deny spiking cigarettes. And tobacco companies routinely deny that cigarettes are addictive. ABC said that it stands by its reporting.

The courts will have to rule on ABC’s story. But the question of spiking is only part of a larger issue: whatever technique cigarette makers might employ, do they manipulate levels of nicotine? If so, what are they trying to achieve? Cigarette companies readily admit that they make products with varying levels of nicotine, from a Carlton to a Marlboro. But they argue that nicotine is merely a natural element in tobacco, and that they vary it only by choosing blends of tobacco, paper and filter systems.

In his testimony, however, Kessler described how the industry has searched for other ways to manipulate nicotine levels. He cited patents for techniques to add nicotine to filters and wrappers and for new chemical variants of nicotine. In interviews last Friday, industry spokesmen tiptoed around the subject of why they file such patents, maintaining that the techniques in them have never been used.

Even if companies do manipulate nicotine, they may not be vulnerable to FDA regulation. The nub of the issue is what the FDA calls “intent.” A product is regulated if the FDA deems that the vendor intends the product “to affect” the body, said Kessler. Afrin clears your nose; Pepto-Bismol calms your stomach. For decades the FDA steered clear of cigarettes, accepting the idea that they were products without purpose. But, Kessler said, that evidence now suggests that manufacturers “may intend that most smokers buy cigarettes to satisfy their nicotine addiction.”

It may be years, if ever, before the FDA decides to regulate cigarettes. Meanwhile the government is developing simpler barriers for the industry. A key congressional committee voted last week to impose a $1.25-per-pack tax on cigarettes. And Labor’s rules would force employers to limit smoking to specially ventilated areas. “It feels like open season” on cigarette companies, said Philip Morris attorney Charles Wall. On that, at least, he may find no argument.