It's a law that was signed in June giving the FDA authority to ban "flavored cigarettes" ostensibly because they are attractive to children. It's been in the works in Congress for years. One of the reasons it's taken so long is that Indonesia has cried foul since as written it covered cloves but not American-made mint/menthol cigarettes, so Congress has been trying to figure out if they can pass it without completely pissing Indonesia off. Apparently they decided so.
I have not yet found any source that says exactly when cloves will be off the shelves, if they will. Though I have read that the importer of Djarum, Kretek, has started making a filtered cigar that apparently looks and tastes a whole lot like a clove cigarette to get around it since the bill doesn't cover cigars.
ETA: Apparently Sept 22 is the date
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