How is the white man's burden a cause for imperialism?
what role did it play in later involvement in foreign affairs ?

White man's burden is the concept which opines that white race is obligated to rule the world and it is the duty of the whites to educate and civilize the world.

Explanation:

It was first used by Europeans colonizing Africa. It is also called paternalism where the Europeans act to be the father figure who heads the family in the poem of Rudyard Kipling. His poem clearly depicts the social ills of American policy towards the Filipinos. It is a Victorian imperial poetry which highlights the European imperialism.

He believed that English man is blessed by the divine will to rule the earth. he advocates that British imperialism is the age of civilization. His poem elevated the spirit of Eurocentric racism. His poem arose the imperialistic power of the Europeans on the world.

to act quickly in times of danger to the united states

because you have to act quickly if you want to live/survive.