Hitler claimed to have studied Clausewitz and Machiavelli, but violated the tenets of both by permitting ideology to override strategy. Hitler's ideology is revealed from documentary sources: Mein Kampf, his speeches, and Tischreden (table talks.) Operation Sea Lion, the planned 1940 invasion of England, was cancelled because the Fuhrer regarded the British as nordic cousins. Operation Citadel, the 1943 Battle of Kursk, was conceived because he decided the racially inferior Slav must be subdued. Doomed from the outset, Hitler nevertheless launched Citadel and squandered most of Germany's remaining armor and elite troops. A general staff officer is interviewed as witness to the period. His background, training, and opinions of the Fuhrer are presented. Thesis conclusion: flawed ideology brought disastrous decisions.