1. World War II: Pacific Theater
Notes from

2. The Pacific Theater

3. Imperial Japan
Japan saw the US and others as a threat to its influence in Asia and in 1940 the Japanese began developing plans to destroy the US Navy in Hawaii
On Dec 7, 1941, the Japanese attacked Pearl Harbor
In May 1940, the main part of the US fleet was transferred to Pearl Harbor from the west coast

4. Pearl Harbor Dec 7, 1941 Americans taken completely by surprise
“a date which will live in infamy”
Americans taken completely by surprise
The first attack wave targeted airfields and battleships
The second wave targeted other ships and shipyard facilities

5. Broader Results
In spite of the tactical success, the attack on Pearl Harbor was an operational and strategic failure for the Japanese
The attack failed to destroy the American aircraft carriers, fleet repair facilities, or fuel reserves
The “sneak attack” galvanized American support for entry into the war

6. Fall of the Philippines
Shortly after Pearl Harbor the Japanese made initial landings on Luzon, then made their main landings on Dec 22
On Dec 24, MacArthur ordered his forces to withdraw to the Bataan Peninsula
By Apr Bataan surrendered
By early May Corregidor surrendered
Douglas MacArthur in his headquarters tunnel at Corregidor in March 1942

7. Bataan Death March
President Roosevelt ordered MacArthur to relinquish command to Lieutenant General Jonathan Wainwright and MacArthur escaped to Australia
25,000 Americans and Filipinos died on the Bataan Death March to captivity

9. Coral Sea (May 4-8, 1942)
US had been able to intercept Japanese radio traffic in an operation called “MAGIC”
MAGIC intercepts allowed Admiral Nimitz to position two carriers off the eastern tip of New Guinea
Both sides suffered heavy losses but the Japanese were forced to call off their amphibious attack on Port Moresby
Battle waged exclusively via air strikes
Opposing surface ships never made direct contact
Admiral Chester Nimitz, Commander in Chief Pacific and Pacific Ocean Areas

10. Midway (June 3-6, 1942)
Japanese planned a diversionary attack on the Aleutian Islands while the main force attacked Midway to destroy the American fleet
Thanks to MAGIC intercepts, US didn’t fall for the Alaska feint and reinforced Midway
Americans destroyed four Japanese carriers and most of their flight crews
Japanese advance was checked and initiative in the Pacific began to turn to the Americans

12. Greatest Extent of Greater East Asia Co-prosperity Sphere

13. Twin Drives
Chief of Naval Operations Admiral Ernest King favored a drive across the central Pacific moving toward Japan over the coral atolls scattered across the Pacific
Take advantage of ability to leap across vast distances
MacArthur favored an advance across the South Pacific via New Guinea and the Philippines
Meet obligations to Filipinos
Maintain pressure against the retreating Japanese
Protect against a renewed threat against Australia
Admiral Ernest King

14. Compromise
King’s planned drive would move first against the Gilbert Islands and then toward the Philippines
MacArthur would likewise advance toward the Philippines
Joint Chiefs gave no clear priority to either drive
“Mutual supporting” or “mutually competing?”
Chester Nimitz, Commander in Chief Pacific and Pacific Ocean Areas and William Halsey, Commander, South Pacific Area and South Pacific Force

16. Operation Cartwheel
Became the model for Pacific commanders throughout the rest of the war
don’t move island to island; advance by great bounds using air superiority
bypass major strongpoints and leave them reduced to strategic and tactical impotence
hit Japanese weak spots; avoid frontal assaults; use deception and surprise
seize existing airfields and ports and use these newly acquired bases to support the next leap forward

17. Retaking the Philippines
The invasion of the Philippines brought MacArthur and Nimitz’s twin drives together
On Oct 20, 1944, MacArthur attacked Leyte

18. Battle of Leyte Gulf
The American and Japanese surface fleets made contact the night of October in the San Bernardino Strait
Two Japanese task forces entered the strait, Halsey did the classic naval maneuver of crossing the “T” and sank all but one enemy destroyer

19. Escort carrier St. Lo sunk by kamikaze attack
Battle of Leyte Gulf
However, Halsey was surprised shortly after dawn when Japanese heavy cruisers and battleships passed unopposed through the San Bernardino Straits and threatened the invasion fleet
American aircraft turned back the already weakened Japanese
Still the Japanese did not give up, delivering their first wave of kamikaze attacks
Escort carrier St. Lo sunk by kamikaze attack

20. “I shall return”

21. Raising the flag on Mt. Suribachi, Iwo Jima
Final Campaigns
From Feb 19 to Mar 11, 1945 the Marines captured Iwo Jima
From Apr to June Americans captured Okinawa
Total American battle casualties were 49,151, of which 12,520 were killed or missing and 36,631 wounded
Approximately 110,000 Japanese were killed and 7,400 more were taken prisoners
Okinawa showed how costly an invasion of the Japanese home islands would be
Raising the flag on Mt. Suribachi, Iwo Jima

22. Operation Cornet, the plan to take Tokyo
Plan to Invade Japan
US planned to invade Japan with eleven Army and Marine divisions (650,000 troops)
Casualty estimates for the operation were as high as 1,400,000
Truman decided to use the atomic bomb to avoid such losses
Operation Cornet, the plan to take Tokyo

23. The Atomic Bomb
In the early 1940s, America had started an atomic weapons development program code named the “Manhattan Project”
A successful test was conducted at Alamogordo in New Mexico in July 1945
J. Robert Oppenheimer and General Leslie Groves at the Trinity Site soon after the test

24. Hiroshima and Nagasaki
Hiroshima Aug 6, 1945
90,000 killed
On Aug 8, the USSR declared war on Japan and invaded Manchuria the next day
Nagasaki Aug 9, 1945
35,000 killed
Okinawa had been much more costly than Hiroshima and Nagasaki
Captain Paul Tibbets piloted the plane that dropped the bomb on Hiroshima

25. Hiroshima, vicinity of ground zero

26. Japan surrenders Sept 2, 1945 aboard the USS Missouri