Where was the power of the rich in the 1930s?

The social safety net is a no-brainer to me. Capitalism has created great wealth and also created great inequality. Starting with Roosevelt in the 1930s, the US built a social safety net, paid for by taxes on the wealthy. The other industrialized nations have all taken the same path. And yet today in the US this concept is under attack. Leading the charge are wealthy Republicans whose personal interest is aligned with lower taxes. But they are also backed by a large number of working people who benefit from the safety net they oppose, acting against their own self-interest. How did this happen? We are told that the wealthy wield great political power, and there is a lot of truth to that.

But how were things different in the 1930s? In Roosevelt's landslide victory in 1936, he won every state except Vermont and Maine. Yet his support was far from unanimous. The popular vote total was 61%, and his Republican opponent got 36%. Over a third of the voters disapproved of him. Presumably the rich were disproportionately represented among that one third, but they had a large minority of ordinary people. Whatever arguments the opponents were making have not made it into the histories I have read. How come the rich lacked power then and yet they have so much of it now?

One of the many things I have been curious about is the US reconstruction of Japan after World War II, carried out in large measure by Douglas MacArthur. The Wikipedia article notes that it was a rare opportunity for one nation to largely remake the society of another nation. Yet while MacArthur was a staunch Republican, the blueprint of society that was imposed on Japan was very much like Roosevelt's New Deal. From Wikipedia, "MacArthur's efforts to encourage trade union membership met with phenomenal success, and by 1947, 48% of the non-agricultural workforce was unionized." Elected Republican legislators might have recognized that the New Deal was so popular with the US electorate that it was unwise to suggest dismantling it. But there was no parallel concern for the views of the Japanese. So perhaps MacArthur was an example of a fair number of Republicans who were convinced that the New Deal was a good idea? Or did they just lack insight, somehow?

In my youth I was earnestly devoted to the goal of a socialist revolution the US. I had enough perspective to look at a wide range of nations where there had been socialist movements, and compare those that succeeded and those that failed. It seemed to me that the key factor in the victory of a socialist revolution was overwhelming incompetence on the part of the existing regime. Where the powers that be had enough political savvy to divide the opposition and buy off parts of it (for instance) the revolutions failed.

So is it possible that the rich in the 1930s just lacked vision and a good PR operation? And that they finally got enough political wisdom to add to their financial advantage to bring about the Reagan revolution of 1980? Or is it possible that through the 1960s they had scruples about just plain lying, and the new generation of right-wing activists lost those scruples?

I would welcome other perspectives on this mystery.