Which policies kept the united states from entering world war i in its first three years?

imperialism and democracy

the monroe doctrine and anti-imperialism

imperialism and neutrality

isolationism and neutrality

Right choice: isolationism and neutrality.

Explanation:

Isolationist views and feelings have always existed in the USA. Isolationism was strong during the first years of  WWI. It was seen as another of those endless and wicked wars fought by selfish European powers. The US public mood changed after a German submarine torpedoed and sank the British liner Lusitania. 1,110 people died, including 120 Americans.