What caused American trade to be cut off from the central powers during ww1?

A major part of the British strategy was to impose a blockade on Germany. American trade with the Central Powers simply could not be permitted. ... It was this situation that prompted submarine warfare by the Germans against Americans at sea. After two and a half years of isolationism, America entered the Great War.

Explanation:

the completion of the erie canal spurred the first great westward movement of american settlers, gave access to the rich land and resources west of the appalachians and made new york the preeminent commercial city in the united states.

im not sure its either a leader of a group of congresspeople or a person from a congressmans district

sorry im not sure