Answer: to prevent accidents from happening
Explanation:
In this scenario, the government would have been forced to take land from white farmers and give it to newly freed slaves.
Many politicians were unwilling to confiscate land from white farmers to give it to blacks farmers because they felt this was a violation of American citizens natural rights. During this time period, ownership of land was seen as extremely valuable as agriculture was still the main source of income for most American families. By taking away someone's land and giving it to someone else, politicians felt that they would be creating an extremely powerful and tryannical federal government. This is why the government never takes farm land and gives it to newly freed African American citizens.
In his "Great Arsenal of Democracy" speech, delivered on 29 December 1940, in the middle of the World War II, Roosevelt portrays the nations of Nazi Germany and its allies as aggressors and with a very different philosophy of government than American's, which consisted of violently dominating the world. He affirmed that If the Axis won the war, they would take over other continents nearby (Asia, Africa, Europe) and would bring enormous military and naval resources against the U.S. as well.
Consequently, the Axis power represented a threat to American society, and thus America, as the great arsenal of democracy, had a duty to help Britain fight the Axis by giving them military supplies while it stayed out of the actual fighting.