Monroe Doctrine and Roosevelt Corollary--the Monroe Doctrine first set the policy that the western hemisphere was closed to colonization. The Roosevelt Corollary took it a step further by providing military behind the policy.
Following the independence movement in the US and throughout Latin America, the US wanted to protect the area from future colonization. The Monroe Doctrine made the statement and then 80 years later the Roosevelt Corollary enforced the doctrine with our navy and army force.
Answer:
the united states emerged following the spanish merica war
B
I believe the answer is: It delayed or extended nationalist struggles.
The nationalist struggles come after different nations started to fully embodied nationalist movement, which make them tend to incline to prove their nation's superiority over another nations. This type of thinking often lead to conflicts among these european nations.