Motte-and-bailey [fallacy]:
The motte-and-bailey fallacy (named after the motte-and-bailey castle) is a form of argument and an informal fallacy where an arguer conflates two positions which share similarities, one modest and easy to defend (the “motte”) and one much more controversial (the “bailey”).[1] The arguer advances the controversial position, but when challenged, they insist that they are only advancing the more modest position.[2][3] Upon retreating to the motte, the arguer can claim that the bailey has not been refuted (because the critic refused to attack the motte)[1] or that the critic is unreasonable (by equating an attack on the bailey with an attack on the motte). [Wikipedia]
The article, above, is fascinating for those who, like myself, have wondered at the advancement of such philosophers as Foucault and their what often appears to be philosophical nonsense. I recall once, long ago, reading that a graduate student assistant to one of them had once muttered something like, “It must be important, it’s so hard to understand!” Unless it’s quantum physics, it shouldn’t be.
Noted in “Two Men Falling,” Andrew Sullivan, The Weekly Dish:
[Biden’s critics] say they’re just decrying the way we left [Afghanistan]; but of course, this is the motte, not the bailey. Read any of their screeds, and you’ll see they still want us to stay. They still think they are right and that the American people are wrong, still believe they have the moral high ground, even as their morality has led to strategic blunders, and hundreds of thousands of innocent deaths. Bill Kristol — I kid you not — actually wrote another article condemning the withdrawal, quoting Churchill and Munich! How dead can a brain be?