In August 1943, Hoover was appointed Commander, Land-based Air, Central Pacific and remained in that command until December that year, when his command was redesignated first to Commander, Aircraft, Central Pacific and then to Commander, Central Pacific Forward Area. He served in this capacities under Fleet Admiral Chester Nimitz during Tarawa, Kwajalein and Eniwetok in the Gilbert and Marshall Islands and Saipan, Guam in the Mariana and Palau Islands. Hoover organized the area of his command for most effective support of future fleet operations and led his powerful land-based strike group deep into hostile territory, bombing and strafing the enemy's formidable defenses in daring offensive operations which materially softened objectives for the amphibious attack forces advancing under cover of his search and reconnaissance planes. He received his second Navy Distinguished Service Medal for his service in these campaigns.