I think they just know that by defining all the people they want to bomb some kind of new version of fascism, Iraq, Libya, Syria, China, Russia, North Korea etc, they can get ignorant left wingers to go along with whatver the next genocide their planning is, just google all those countries names next to the word fascism, you will find some angry racist white propagandist declaring their leader the new Hitler. So if you ever question their latest bombing campaign plans, no matter how insane it is, they will simply declare them the new hitler, find some minority being oppressed, if their sunni say they are oppressing the shia, if they are shia the opposite. find some mistranslated quote about israeli apartheid maybe, throw in a little pinkwashing and boom you’ve got the next hitler and anyone who defends him is now also hitler. It simultaneously excuses all the war crimes committed against these people, for example the US has killed millions of iraqis probably tens of millions when you add in deaths from disease, malnutrition, lack of medical care etc. Yet they are never described as hitler, in fact even self described leftists in the US will commonly say that Iraq is better off without saddam because he was such a nazi. Yet to even describe the most racist US politician as fascist is heresy.