> The government acted legally. That was (and in a lot of cases still is) the problem.

Sure - I understood "dog bites and hoses" here to be a synedoche for the general government and civilian response to the civil rights protests, some of which was legal and some of which was not. Obviously I don't know the specifics of your teachers' particular stories.

It's easy to write off those atrocities with "that happened, but it was dealt with, and it's in the past now" - which, as you pointed out in the other comment, is a convenient lie. My main point was that these were not isolated incidents (as GP implied), and that - whether legal or not - those involved faced few consequences (if any) for their actions.