I was thinking about all the wars and conflicts which occurred in the 20th and 21st century. It seemed like a lot of territory conquered over this 100-odd years was only briefly held.
In WWII in particular, even though Germany and Japan took large amounts of territory relative to their size, neither was able to hold it for longer than a few years at most.
I know that the US played a big part in the latter part of WWII, but I’m wondering if the inherent challenges of occupying conquered (as opposed to liberated) territory was a bigger factor. Obviously if you are going to have your country gobble up your neighbor, you are going to need:
1.) A military force which is strong/organized enough to quickly overwhelm them
2.) Popular support at home
3.) Good intelligenge and counterintelligence to know when/where to fight
4.) Forcing the conquered nation into some alliegance with your own
Before someone beats me to it and mentions the Soviet Union, I will also say that they seemed to demonstrate the only feasable way to take and hold another coutnry for some time- wait for it to get beaten by some other nation/alliance in a previous war. That, and the newly established nuclear deterrent seem to allow them to pull it off for as long as they did. Though the US had a head start on nukes, so I’m wondering why they didn’t put more pressure on the Soviet Union when they had the chance…