Fox News has an article entitled "Biden administration's proposed menthol cigarette ban could become liability in 2024: 'Unintended consequences.'" It goes on at some length and only hints at what was on the author's mind, never says it in clear unambiguous English.
To really understand the argument being made you also need to be aware of the following statistics, published in the science journal Nicotine and Tobacco Research and echoed here on a website maintained by the National Institutes of Health.
In 2020, 43.4% of adults who smoked cigarettes in the past month used menthol. Menthol use was most common among black adults (80%) and over 50% of those Hispanic, female, young (ages 18–34 years), lesbian/gay, with serious psychological distress, and with cigar use used menthol.
Who are the big time menthol cigarette users? As noted above, blacks, Hispanics, women, young people, LGBTQ+ individuals. Does that also sound like a list of the groups Democrats depend on for winning elections? Damn straight, it does.
You don't have to be Karl Rove to understand the undesirability of flipping off the very groups which are your core constituencies. The article hints at this connection, but never states it in so many words.
That is the very essence of a political dog whistle. Signal to the cognoscenti that you know and you know they know, but you never say it so you can't be quoted out of context and called "a racist."
