Hawaii's Sugar Industry and Pineapple Industry were making HUGE Profits.  The other Greedy 48 U.S. States wanted some of those profits.  The best "Legal" way was to create a U.S. Law, Merchant Marine Act of 1920, as the Residents of Hawaii did not have any Political Clout to Oppose anything, including Legalized  theft of their Money by the 48 U.S. States.

continued, Merchant Marine Act of 1936.