I’ve always thought of these as basically a protection racket. Probably not literally, but close enough.

First they came for the socialists, and I did not speak out—
Because I was not a socialist.
Then they came for the trade unionists, and I did not speak out—
Because I was not a trade unionist.
Then they came for the Jews, and I did not speak out—
Because I was not a Jew.
Then they came for me—and there was no one left to speak for me.

What’s the point?