The Holocaust was suddenly in the center of U.S. political discourse early this week. Rep. Alexandria Ocasio-Cortez (D-N.Y.) referred on social media to U.S. Customs and Border Protection (CBP) detention centers as concentration camps, which provoked a backlash from conservatives and then a flood of support from liberals. And #Kristallnacht trended on Twitter on Monday night after President Trump tweeted that U.S. Immigration and Customs Enforcement (ICE) will soon step up its work “removing the millions” of undocumented immigrants, seemingly signaling an escalation of his administration’s tactics aimed at migrants.

Are these analogies just? Is it really reasonable to compare what’s happening with immigrants under Trump to the Third Reich? Or should the Holocaust be off-limits for comparisons to current events?

If done with caution, those analogies can be useful. Looking at Holocaust history — thoughtfully, carefully — can help us to see the parallels between then and now. It can also help us to understand when those parallels are not apt, and what that does and doesn’t mean about news as it breaks. Of course, analogies are imperfect, and every situation has its own nuances and context, but looking at monstrous events of the past can help us understand where we are in ways that can be difficult to see in the day-to-day.

Some who criticize drawing parallels between the United States today and Germany of the 1930s suggest that doing so demeans the memories of the Jews, political dissidents, LGBT, disabled and Romani people and others targeted by the Nazis — that not every instance of oppression is genocide, and using this kind of language diminishes the suffering under Hitler.