The Pacific was divided into two "Theaters" of Operations - the Central Pacific, and the Southwest Pacific. This was done mostly because MacArthur had retreated to Australia after Japan conquered the Philippines, and as a former commanding general of the US Army, a prestigious command had to be carved out for him. So, MacArthur commanded in the Southwest Pacific, fighting in the New Guinea area and the Philippines. Navy Admiral Chester Nimitz commanded in the Central Pacific, from his HQ in Hawaii, where he was also commander of the US Pacific Fleet.
US was attacking in the island hopping campaign, not Japan. Japan was defending. Island hopping started midway, and went through Iwo Jima, Tarawa, and so on. again, US was attacking.
Japan
Island hopping.
Okinawa
"Midway" was strictly a naval battle. Iwo Jima was part of the "island hopping" campaign.
Okinawa
Okinawa
Okinawa
Okinawa
Okinawa
Okinawa
Midway