The correct answer to this open question is the following.
The geographic feature of Mesopotamia that led to the Sumerians being easily taken over was the Tigris and Euphrates Rivers that made it easy for their enemies to navigate and invade them.
Sumeria was the oldest civilization known to man. Sumerians settled in the middle of the Tigris and Euphrates Rivers in the Middle East region. There, they developed agriculture techniques and learn how to use the flood of the rivers to grow crops in that fertile soil. That is how they prosper for some time until their enemies could access their city-states navigating through both rivers.
It looks like the cartoon is sort of mocking the Nazis. Or comparing it to America. You can tell my the symbol of the dude on the right’s shirt..
Is this a random Nazi official? Going to go on a limb and say Argentina because apparently a few escaped to their.