Hindsight is a wonderful thing.
In establishment circles, both sides of the Atlantic, the Nazis were in vogue with a number of high profile individuals in the 1930s, but this was more a product of those politically chaotic times, the old certainties gone, where the fear of Bolshevism gripped figures like 1st World War Prime Minister Lloyd George "the man who won the war"
In 1936, Lloyd George visited Germany and met with Hitler twice. He admired Hitler's ability to reduce unemployment, and by the country's overall economic and social conditions. He was impressed by the "universal adoration" of Hitler throughout Germany. He said he had never seen the Germans "happier". He called Hitler "one of the greatest of the many great men I have ever met". He also described Hitler as the "George Washington of Germany".
I'm no expert on US politics of the 1930s, but if you believe, as I do, that capitalism in America has two political wings, the Democrats and the Republicans, then communism has always been seen as a greater enemy than fascism, and that includes the war years. It's a myth that the USA, or the UK for that matter, fought the second world war primarily to defeat fascism. In the post war years we were more than wiling to turn a blind eye to fascists if they were a useful bulwark against communism, particularly in the newly independent nations of the post colonial world.
Those inter war years are greatly misunderstood and viewing them through a post war prism is a waste of time.
A Nazi rally held in Madison Square Garden, February 20th 1939