General Ripper, despite being a common trope, is actually fairly unrealistic. For centuries, militaries have operated on a strict hierarchy. Any single person, no matter how highly ranked, cannot act if overruled from an even higher ranked entity — including the leader himself. Any soldier who will act unilaterally and ignore orders is not a good soldier.
The phenomenon actually emerged as late as World War II, when the British and American political leadership permitted senior officers to undertake operations and campaigns more or less at their own discretion. This occasionally led to the military doing things the generals didn't like at all — for instance, Winston Churchill was appalled at the firebombing of Dresden and other German cities, but he couldn't do anything about it. U.S. Secretary of War Henry Stimson found out about the firebombing of Tokyo from the newspaper. But it doesn't really fit the spirit of the trope, as these actions were technically authorised, even if they weren't what the generals themselves would have done if they were actually the ones giving orders.
The essence of General Ripper is a rogue officer who overrules their superiors, or at the very least desires to do so. This is difficult to do in an ordinary military environment, as military operations tend to be highly complicated and intricate. All sorts of disparate units and formations have to be acting in sync, which requires tight oversight. It therefore becomes practically impossible for a single rogue general to do anything unilaterally beyond the small number of people over whom he has direct authority. For instance, if General Ripper wanted to undertake an aerial bombardment like in Dr. Strangelove, in Real Life he'd have to procure up-to-date information about the target area, enemy assets, and support capacity, all of which come from other units outside his control. The only way General Ripper could go rogue would be not to act at all when ordered to, and in Real Life this is the most common sign of a rogue general.
