Sugar plantations were the of the economy. sugar was also the main hawaiian export to the united states. for many years, hawaiian sugar was sold tariff-free in the united states. in 1890, the us congress passed the , which removed tariffs on all foreign sugar imports. this change meant that hawaiian sugar producers had to compete with other nations in the us market.

when world war i broke out across europe in 1914, president woodrow wilson proclaimed the united states would remain neutral, and many americans supported this policy of nonintervention. however, public opinion about neutrality started to change after the sinking of the british ocean liner lusitania by a german u-boat in 1915; almost 2,000 people perished, including 128 americans. along with news of the zimmerman telegram threatening an alliance between germany and mexico, wilson asked congress for a declaration of war against germany. the u.s. officially entered the conflict on april 6, 1917.