Andrea Pitzer, an author who has written about the history concentration camps, on Tuesday’s broadcast of “All In” on MSNBC, echoed Rep. Alexandria Ocasio-Cortez’s remarks that compared what is going on at the southern border to concentration camps — comments that have been met with pushback.

Host Chris Hayes introduced Pitzer as someone “who is qualified to weigh in on” Ocasio-Cortez’s comparison.

Pitzer then said what is being done now at the border “fits very cleanly” with what happened in concentration camps

“I would say that for 40 years before Auschwitz, we had concentration camps, things that were called concentration camps — what we’re doing now fits very cleanly inside that tradition,” Pitzer told Hayes.” At the same time, the death camps, which were on top of the existing concentration camp system, including Auschwitz and a series of other camps in which you had gas chambers, mass killings, that is a singular moment in history. And for the people who want to respect that, I think that’s fine, and that’s important.”

She continued, “If we want to call it irregular detention, if we want to call it extrajudicial detention, I don’t think we have to get stuck on that term. I wrote a history of the term. I had to use that term. And what I would really like people to know is the same thing is happening here now.”

Pitzer added that the crisis at the border is not a national security crisis, but rather a “humanitarian crisis” in a “war setting.”

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