The idea that the LBJ government was, in a certain way, the progressive one instead of JFK was also indicated in this SPGB article, used to debunk the propaganda that Kennedy was a liberal and that he supported the civil rights movement
He is already saying, if he can’t tax the rich class, he is going to tax he middle class, but which middle class ? The middle class does not exist, probably he means the working class, but the state is an institution financed with surplus value. He economic reality is showing to him and the DSA that capitalism can’t be reformed to benefit the vast majority of the workers.