Franklin Roosevelt set up the lend-lease program in 1941 to
help Britain fight against Germany and the Axis Powers. The United States was
officially uninvolved in the war at the time but this was a method of offering
aid indirectly to the Allied nations.
The Constitution didn't specify if the Vice President were to become President if the President died, resigned, or got impeached.
The answer is quest for riches
By extending their arguments to address entire nations, some social Darwinists justified imperialism on the basis that the imperial powers were naturally superior and their control over other nations was in the best interest of human evolution.
Richard Nixon created this