Why did the United States pursue different leadership over Cuba v. Puerto Rico v. the Philippines?

Summarize the effects of the marshall plan on the us and western european countries

How did the union blockade of the southern coast affect the confederacy? it forced the confederacy to build new railroads. it contributed to shortages of weapons and food. it encouraged europe to trade with the south. it halted all trade, leaving the south without supplies.

Why is it useful for historians to base certain studies on the analysis of historical periods