A progressive who stays home on Election Day — or backs Robert F. Kennedy Jr., Cornel West, or No Labels — is voting for Donald Trump.
"Progressives should not make the same mistake that Ernst Thälmann made in 1932. The leader of the German Communist Party, Thälmann saw mainstream liberals as his enemies, and so the center and left never joined forces against the Nazis. Thälmann famously said that 'some Nazi trees must not be allowed to overshadow a forest' of social democrats, whom he sneeringly called 'social fascists.'
After Adolf Hitler gained power in 1933, Thälmann was arrested. He was shot on Hitler’s orders in Buchenwald concentration camp in 1944."
That's historical revisionism. They would have easily created a coalition government to oppose Hitler, but without the support of the communist party, the conservative block ultimately held onto control, and Hitler was appointed chancellor by Hindenburg.
You're disingenuously conflating the conservatives that ceded power to the Nazi party (that had only taken about 30% of the vote) with the center left that reached out to the communists in an attempt to stop them. A decision by the head of the communist party that directly led to the murder of millions of people, including himself.
We are talking about a parliamentary system. The communists could have formed a coalition government that had a majority, but they refused. Without their support, no party won a majority or were able to form a majority coalition government, and the Nazis were able to take control from the conservatives in power (or more accurately, they gave it to them freely).
I'm not a historian, so someone correct me if I'm wrong.
No, at no point did the Centre try to form a coalition with the KPD, but were turned down. In the Weimar system, it is the Chancellor that is in charge of forming coalitions, so even if the KPD, SPD, and Centre had enough seats to form a majority (which they didn't), they couldn't just form a coalition. This is why Franz Von Papen was appointed by Hindenburg, since he was expected to be able to convince the Centre party and Nazis to form a coalition with the conservatives and monarchists. And why when that failed and there was a failure to form a ruling coalition that Hindenburg appointed Hitler as chancellor to create a Nazi lead coalition.