How did nations confront foreign aggressors in world war 2

1: how did the rise of rulers with total power in europe and asia lead to world war 2?

All of the following effects occurred as a result of roman expansion following the punic wars except it brought in great wealth from conquered territories it allowed many romans to buy large farming estates it provided slave labor for the large farming estates it caused the roman economy to decline due to the high cost of war

What is the name of the first president