Rudolf Hess never joins the Nazi Party. Does Lebensraum still become a pillar of Nazi ideology?

In our timeline, the Nazi obsession with Lebensraum (living space) began with Rudolf Hess, who was a student of Karl Hanhofer, who postulated the idea of Germany expanding East to gain more territory to create settler colonies.

So if for some reason, Rudolf Hess never joined the Nazi Party or if Karl Hanhofer was never born, what happens to the idea of Lebensraum? Does it still become a pillar of Nazi ideology? If it doesn't, how does the absence of this idea affect the development of National Socialism?
 
Yes, he did. But it's my understanding that when Rudolf Hess joined the Nazi Party, he brought the idea of Lebensraum with him. Hess was a Nazi Party member before Mein Kampf was written.

Couldn't he just as easily have gotten the idea from Rosenberg and others? True, "The final elaboration of Hitler's programme for acquiring Lebensraum occurred while he wrote Mein Kampf during 1924-1925. Essentially, this involved his study of 'geopolitics', that is, the impact of the environment on politics, which provided him with a quasi-scientific justification for the plans he had already worked out. During his period in Landsberg prison (where he had been incarcerated following the failure of his notorious Munich beer hall coup in November 1923), he read and discussed Ratzel's work and other geopolitical literature provided by a Munich Professor of Geography, Karl Haushofer, and fellow-prisoner Rudolf Hess." http://www.bbc.co.uk/history/worldwars/wwtwo/hitler_lebensraum_01.shtml But this was only an elaboration of a concept that Hitler already had:

"To begin with he was not hostile towards Russia, and saw Britain and France as Germany's main enemies. Indeed, during 1919, he blamed Germany's pre-war politicians for supporting Austria-Hungary against Russia.

"But by 1920 he was arguing that 'an alliance between Russia and Germany can come about only when Jewry is removed', and, by 1924, when he came to write Mein Kampf, he had concluded that Russia would be the target for Germany's drive to acquire Lebensraum. So how did this change of approach come about?

"Hitler's views on Russia during these early years were strongly influenced by Alfred Rosenberg, who had joined the Nazi party in 1920 and became the editor of its newspaper, the Völkischer Beobachter. Rosenberg was a Baltic German who was studying in Moscow when the Russian Revolution broke out in 1917, and left Russia for Germany in November 1918.

"Thus he had experienced the Bolshevik revolution at first hand and became convinced that it was the work of the Jews. Hitler considered Rosenberg an expert on Russia and became equally persuaded of the link between Bolshevism and the Jews.

"By 1922, it was becoming apparent that the Bolshevik regime in Russia was there to stay. Indeed, it is clear from an interview Hitler gave in December 1922 that by then he had decided that an alliance with a Bolshevik Russia was out of the question. Germany would be better off working with Britain and Italy, which appeared to be resisting French hegemony in Europe, against Russia, which could in turn provide Germany's necessary Lebensraum. Hitler's views on Russia had been further hardened by his contacts with Baltic German exiles in Munich. Notable among these was Max-Erwin von Scheubner-Richter, a contact of August Winnig, the German Commissioner in the Baltic provinces responsible for organising the Free Corps, and General Ludendorff, the former leader of Oberost.." Ibid.

Now maybe Hess had already introduced the concept to Hitler by 1922, before their stay in prison. But it still seems to me at least as likely that Hitler got it from Rosenberg or other Baltic German exiles from Russia.
 
For a longform meditation about why Hitler simply inherited existing colonise-the-east-at-all-costs German ideology, a book I've recommended here before, 'Exterminate All The Brutes' by Sven Lindqvist.

Or, for a brief educated UK perspective of the same thing, this book review by James Hawes in the Spectator the other day:

Even Germans easily forget how far eastwards Germany used to go. East Prussia, the spiritual and often literal home of the Prussian military elite, was east of Poland. My wife’s late father was brought up there as one of them, in what’s now Russia, and he recalled the utterly colonial and therefore highly militarised life the Germans there had lived for centuries. A Germans vs Slavs showdown was never far from Prussian minds. Fifty-odd years before Operation Barbarossa, members of Wilhelm II’s Prussian elite discussed kicking Russia out of the Baltic, getting their armies to the Volga, setting up a puppet Ukraine, and reducing the tsars to vassals.

This explains why all the people who killed their families were eastern Germans. With such old and bad blood, and knowing full well (as many must have) what the regime they’d voted in had done to their Polish neighbours, eastern Germans had good reason to suspect that when the showdown went wrong and the vengeful helots came charging in, there truly might be fates worse than death. This was nothing to do with psychology and everything to do with the thing that can safely be left to speak for itself: history.
 
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