[3][4] When a torpedo hit the port bow of the Arizona, Shapley was thrown from the foremast at least 100 feet through the air into the water; he was able to swim to Ford Island and to rescue two shipmates along the way.

Two days after the attack on Pearl Harbor, Shapley sailed for San Diego to become personnel officer to the Amphibious Corps, Pacific Fleet.

Shapley was awarded the Navy Cross for extraordinary heroism as a lieutenant colonel, commanding the Fourth Marines (Reinforced) on Guam from July 21 to August 10, 1944.

His Navy Cross citation states in part: Courageously leading his regiment in an assault landing against strong enemy beach defenses, Lieutenant Colonel Shapely rapidly seized the assigned beachhead and defended the area against fanatical hostile counterattacks.

Following the Okinawa campaign, Colonel Shapley has been relieved by Lt. Col. Fred D. Beans and ordered back to the United States in July 1945 to become Assistant Inspector in the Inspection Division at Marine Corps Headquarters, Washington, D.C.

In that capacity, he accompanied Admiral William F. Halsey on an official goodwill tour of Central and South America from June to August 1946, receiving decorations from Chile and Peru during that assignment.

After graduation from the War College in June 1947, Colonel Shapley served for two years at Norfolk, Virginia, as assistant chief of staff, G-3 (Operations and Training), of Fleet Marine Force, Atlantic.

In January 1951, Colonel Shapley was ordered again to Washington where he served on the International Planning Staff of the Standing Group, North Atlantic Treaty Organization, until June 1953.

In 1953 Shapley was ordered to Korea; he served as chief of staff, 1st Marine Division, earning the Bronze Star with Combat "V" for meritorious achievement during this period.

For subsequent service as senior advisor to the Korean Marine Corps, he was awarded the Republic of Korea's Ulchi Medal with Silver Star.

After holding this post for over two years, he returned to the West Coast in November 1959, and served as commanding general, Marine Corps Base Camp Pendleton, until March 1961.