A new rule by the FDA could change smoking as we know it.No drug is quite like nicotine. When it hits your bloodstream, you’re sent on a ride of double euphoria: an immediate jolt of adrenaline, like a strong cup of coffee injected directly into your brain, along with the calming effect of a beer. Nicotine is what gets people hooked on cigarettes, despite their health risks and putrid smell. It is, in essence, what cigarette companies are selling, and what they’ve always been selling. Without nicotine, a cigarette is just smoldering leaves wrapped in some fancy paper. But if...