It would be all of these. During world war 2 it is the United States that supplied almost everything in the allied war effort. Also the United States take longer route and also a hard campaign to combat the German U-boat for supremacy and stable supply route for the allied forces.
Corrupt leaders made the democracy of Rome compromise itself and led to monarchy and then sometimes to ruin
Explanation:
The Democracy of Rome had many intricacies that excluded a number of people from ever participating and made it in a way an exclusive group that could ever hope to hold political power.
This made it easier for the government to be very corrupt and they had very little accountability.
The people became dissatisfied and thus many times supported the foundation of monarchy or even found the city in state of civil war multiple times in centuries.