Why did king kalakaua give pearl harbor to the US?

Answer 1

The Hawaiian League forced him to sign the bayonet constitution.

Answer 2

King Kalakaua of Hawaii did not personally give Pearl Harbor to the US. The decision to allow the US to use Pearl Harbor as a coaling and repair station was made by his successor, Queen Liliuokalani, in 1887 through the agreement known as the Reciprocity Treaty. The treaty was motivated by economic benefits and the desire to maintain good relations with the powerful United States.