National _________ German Workers' Party
Sounds a little like he opposes capitalism, wouldn't you say?
This is not exactly true. And to understand this, you need to look at Socialism in the early to mid 20th century.
Now to modern Socialists-Communists, it is pretty much Religious Canon that when Marx descended from the Heavens he handed the books of Socialism-Communism off to Lenin, who then made a true Worker's Paradise on Earth with them in the form of the CCCP-USSR. But the problem with this is that it is entirely taken from the beliefs of Communists. They like to believe that all Socialism came from Communism, and leads to Communism. And that there is no Socialism without Communism.
And like any canonical religion, they are quick to label others as heretics, and scream that they are not "True Communism" or "True Socialism".
They do not like being told that Socialism existed before Marx was even born, and his is not the only definition of the word. During the Early and Mid-1900's, there were a great many variants of Socialism. In fact, the first such National Socialist nation was probably the Kuomintang under Dr. Sun Yat-sen. Dr. Sun was very much a Socialist, in the vein of the Second International and other organizations that followed classical Socialism, but largely ignored the additions added to it by Marx.
This is where you get the real split, and one that most Socialists will deny to their dying breath ever exists. Myself, I call it "National Socialism" and "International Socialism". The International part is obvious, those are the Marxists. The vast majority of the others tend to follow a form of Socialism that avoids any attempts to link them all together, to create a "One World Government", an "International Soviet", or whatever other kind of buzz words they like to throw into it.
Republic of China, Italy, India, Burma, Iraq, Egypt, not all Socialist countries are or were Marxist. But the Marxists pretend like they do not exist. Kind of like the family of a Catholic Priest who leaves the clergy and converts to Presbyterian. Or members of a Baptist congregation that see each other in a bar.
NSDAP Germany very much was a Socialist nation. However, it was not a Marxist-Communist nation. Reading the platform of the party both before and after der Paper Hangar entered the picture show that this was the case. Anton Drexler (the founder) was an anti-Semite, a Nationalist, and a Socialist. He was also an anti-Marxist. And anybody who has ever actually read the "25 Point Program" can not deny that it is fundamentally a Socialist agenda.