Why is Abraham Lincoln Adolf Hitler's favorite President?

• Great means big.
• Lincoln preserved the Union (what Lincoln himself said his main task was) leaving a much stronger state.
• He did it by successfully fighting a years-long bloody war much larger than any in Europe in 1815-1914, while at the same time building the first transcontinental railroad and booting France out of Mexico. What's not to like for Hitler?
• Hitler cared little about faraway Africans or African-Americans, who anyway appeared to be firmly under white control at the time.
• What Hitler really admired was the example of Anglo-Americans conquering and populating a continent. After this stupefyingly fast change in the world's composition, conventional wisdom became that peoples had to expand to survive. Hitler wanted this kind of continental expansion for Germany, even if the indigenes to be exterminated were not Native Americans or Arabs in Algeria or Australian Aborigines, but many of the whitest peoples on the planet.

It's stretching things to say that Abraham Lincoln was a favorite of Adolf Hitler. Hitler was an authoritarian who believed in racial hierarchy as a core principle.

According to Civil War historian Don Doyle in his book The Cause of All Nations: An International History of the American Civil War, Hitler definitely favored the Confederate side of things:

In 1933, during an after-dinner discussion in Munich, Adolf Hitler bemoaned the South's defeat in chilling terms: "The beginnings of a great new social order based on the principle of slavery and inequality were destroyed by that war, and with them also the embryo of a future truly great America that would not have been ruled by a corrupt caste of tradesmen, but by a real Herren-class that would have swept away all the falsities of liberty and equality."

The obvious answer is that Lincoln was our greatest nationalist. To Hiltler Lincoln thought in absolute terms. No matter the cost in blood Lincoln was determined to subdue the South. You must remember that Lincoln was characterized as a tyrant by the Copperhead press, as well as the British press. Throughout the 20th century a steady stream of venom has been spewed upon Lincoln for being worse than George III, by the likes of the former president of William and Mary College, Lyon Gardiner Tyler, son of  president John Tyler and the premiere Southern agrarian neo-confederate conservative Mel Bradford. That would have endeared Lincoln to Hitler even more.