Jarvis Island, Kingman Reef, Palmyra Atoll, Johnson Atoll, Midway, Wake Island, Guam, Baker Island, American Samoa and several others. Hawaii is part of the US and is not "owned" by the US.
See the Wikipedia link below for the list of U.S. territories (not just those in the Pacific).
2,300 islands are governed to the US
about 2300. I don't know where you get 2300 but according to the U.S. Geological Survey there are 18,617 named islands that are part of the United States and its territories! That is not counting the many Many MANY un-named islands of witch no one knows the exact number.
United States has 200 islands
The Hawaiian islands compose of Hawaii, one of the fifty states.
The Hawaiian Islands make up the US state of Hawaii.
The United States has several island territories, including the U.S. Virgin Islands and Puerto Rico in the Caribbean Sea and Guam, American Samoa, and the Commonwealth of the Northern Mariana Islands in the Pacific Ocean. There are also several U.S. islands in the Pacific with no permanent inhabitants, including Midway Island.
The US did not mine anything in these islands.
The Cayman Islands were never part of the United States.
There are many: https://en.wikipedia.org/wiki/List_of_islands_of_the_United_States
Hawaii is ranked #43 in area among the US States.
The United States took possesion of the Midway Islands.
No. Cayman Islands are not a part of the United States and have no relation to the banking industry in the US