I will register a bit of a contrarian take on the events over the weekend (at least, contrarian for this board). While I am no supporter of Trump in general or his immigration policies in particular, I am not ready to equate non-lethal crowd control measures directed at people rushing our border security with the Holocaust. Open borders theorizing aside, large majorities of the American people want reasonably secure borders and do not want to see masses of people rushing across while law enforcement authorities stand aside. Naturally I would prefer that the United States do much, much more to prevent these scenes ever happening in the first place. For starters we could have a rational and proactive immigration policy that isn't riddled with racism. Failing that the Trump administration could and should allocate resources to the border so that asylum claims can be processed at a quicker pace, and could and should provide humanitarian aid to the people stuck in Tijuana waiting on the glacial pace of asylum admissions.
Nonetheless, and despite the fact that Trump could have done more to prevent the rush ever happening, an attempt to forcibly cross the border did occur. Defending the border in this manner is far from the worst possible outcome and I am not sure that past administrations would have done anything much different faced with the same circumstances.