Surely, there must have been a significant amount of high ranking civil and military Germans who thought Hitler's plan of waging wars of aggression against most of the world and committing genocide was either 1) unethical or 2) ignoring ethics, was a bad idea for Germany. So why didn't more Germans oppose Hitler?
There is a certain idea that goes around much of the generals, field marshals, and other high ranking officer of Germany. Much of it tends to focus on why the didn’t oppose Hitler sooner or object to the atrocities during the war. This is furthered by post-war memoirs and interviews with surviving German generals . But this covers up the fact that many did not disagree with Hitler, but instead agreed with his plans and went along with them.
Many of the German generals agreed with Hitler’s view on Judeo-Bolshevism. This is the idea of a greater Jewish conspiracy to control the world with Communism. That every Jew was trying to take over the world, and the Germans were the ones trying to save the world. Germans from private to field marshal believed in this idea and saw themselves not only as saviors, but to see the Jews as sub-human. The other threat was the Soviet Union in general; just as Russia in 1914, there was a slight fear of the Russians one day attacking Germany with renewed strength. Though these fears were put down a bit after the Purges and the Winter War. The threat of Russia was real and the sooner they dealt with the problem, the better. When the invasion of the Soviet Union began, they were cooperating with Hitler to weed out the “undesirables” in occupied territory. Like I stated before, many of these generals believed in exterminating Communism and the Judeo-Bolshevik threat.
While the Generals and Hitler generally agreed on this, they couldn’t agree where to focus on during the invasion. Hitler wanted secure the North and South first, then take Moscow. The generals and the high command wanted Moscow to be taken first. This became a huge split with Hitler and the High Command. Hitler now interfered more and more in Wehrmacht plans and attacks. However the High Command would routinely take troops meant for Leningrad or Case Blau and give them to Army Group Center at Rzhev by 1942. Rzhev was close to Moscow and an important transport hub. With Rzhev held, they could strike at Moscow again soon. But this was fully out of Germany’s reach now. High Command would continually edge Hitler or try to sneak past him troops to this area. And much of the times Hitler would agree. The generals here could easily get around Hitler and work him in ways to get what they wanted. As long as they didn’t overstep their bounds and agreed with some of his plans. But this could be the reason why the Germans
Certain generals like Halder and Guderian are well known critics of Hitler, but during the early stages of the war and even before the war they believed in Hitler. Even Rommel who is the poster child of “Clean Wehrmacht” was appointed by and was very close to Hitler. Many of these generals were very close to Hitler and while they sometimes butted heads, they did work with him. They were fine with committing atrocities and devastating occupied territory with Hitler in charge. However with Hitler dead, and much of the Allies and other conquered territory wanting to bring Nazis to justice; the idea of the Clean Wehrmacht was born. Now these surviving German generals could write their “side” of the story. With no Hitler to refute these claims and those that could not wanting to be ousted, men like Guderian and Halder could get away with much. Not only this, but the Western Allies needing a strong West Germany to oppose the USSR raised up certain Wehrmacht generals and forgave the rest.
While later on you might be able to see the cracks in the German High Command and their loyalty to Hitler, in the early days it was basically non existent. The officer corp and the High Command were in align with Hitler about the Russians, communism, and Jews, it was only when Hitler started to interfere more and more in military affairs could cracks be seen.