There is no number of foreigners that is unacceptable to sacrifice for a middle class livelihood. Anti-cop because they can imagine a scenario where a cop inconveniences them. These principles don't apply to the Waffen SS because they can't imagine a soldier personally inconveniencing them and, of course, foreigners aren't really humans.
This kind of strategy is great if you can swing it, but it requires a large organized and disciplined leftist party that the US has never had. Part of the reason why we over focus so much on individual choice is because the capacity for anything else has been burned out of American society by the conditions of American capitalism.