1. One reason would be the United States came into the  Hawaiian territory for their economic advantages such as sugar crops , not really caring about Hawaii's opinion 
2. The American whites applied for the annexation  without Hawaii's authorization .
3. The united states overthrew Queen Liliuokalani, and took over the government  

1.) The Open Door Policy did little to rid China of continual foreign interference in ancient customs and foreign disregard for Chinese culture and society. 

2.) The imperialist nations demanded that China give them special trade privileges and lease them on land.

3.) At a certain point they just stopped trying to enforce the policy, "Today we are the poorest and weakest nation in the world and occupy the lowest position in international affairs. Other men are the carving knife and serving dish; we are the fish and the meat. "   

-America had engaged china in trade,without entirely invading their nation.
-America had tried to benefit by making the Open door policy.
-America had wanted to benefit economically along with getting on good terms with them.
-China had been vulnerable which is why America had  tried to involve itself with them.they mainly wanted to benefit.