THE ALLIED ADVANCE IN THE PACIFIC

1. THE ALLIED ADVANCE IN THE PACIFIC ISLAND-HOPPING TOWARDS JAPAN, 1942-44

2. IMPORTANT DATES • AUG., 1942- FEB., 1943: • U.S. ASSAULTS / RETAKES GUADALCANAL • NOV.,1942- JAN.,1943: • ALLIED CAMPAIGN / CONQUEST OF NEW GUINEA • APRIL, 1943 – JUNE, 1944: • OPERATION CARTWHEEL • NOV., 1943: BATTLE OF TARAWA • JUNE,1944: • THE BATTLE OF SAIPAN • BATTLE OF THE PHILIPPINE SEA • “THE GREAT MARIANAS TURKEY SHOOT”

3. IMPORTANT TERMS / PEOPLE • ADMIRAL CHESTER H. NIMITZ • GENERAL DOUGLAS MacARTHUR • ADMIRAL WILLIAM F. HALSEY • THE SOLOMON ISLANDS • GUADALCANAL • “THE TOKYO EXPRESS” • NEW GUINEA • “ISLAND –HOPPING” • OPERATION CARTWHEEL • TARAWA • “THE GREAT MARIANAS TURKEY SHOOT”

5. PACIFIC SITUATION, SUMMER, 1942 • JUNE, 1942: BATTLE OF MIDWAY: • IJN IS DEALT 1ST MAJOR LOSS OF WWII • U.S. NAVY ACHIEVES 1ST MAJOR VICTORY IN PACIFIC • JAPANESE ADVANCE IN PACIFIC IS STOPPED • PROBLEM: • JAPANESE EMPIRE IS STILL AT IT’S GREATEST EXTENT • JAPAN STILL CONTROLS MOST MAJOR ISLANDS IN PACIFIC • AUSTRALIA IS STILL THREATENED BY JAPANESE • JAPAN HAS EXTENSIVE NETWORK OF FORTIFIED ISLAND CHAINS THAT MUST BE TAKEN • WHY? • NO INVASION OF JAPAN IS POSSIBLE UNTIL ISLANDS ARE TAKEN • ISLANDS CAN BE USED AS NAVAL AND AIR BASES • RESULT? ALLIES MUST FORM PLAN TO… • ASSAULT / SEIZE JAPANESE-CONTROLLED ISLANDS • ASSAULT & POSSIBLY INVADE JAPAN

6. PLANNING THE ADVANCE • PROBLEM: • WHAT WAS THE BEST WAY TO DEFEAT JAPAN? • WHAT ROUTE SHOULD THE ALLIES TAKE TO ADVANCE TOWARDS JAPAN? • NORTHERN ROUTE VIA N. PACIFIC ISLANDS? • SOUTHERN ROUTE THROUGH LARGER S.PACIFIC ISLANDS? • DECISION: THE SOUTHERN ROUTE • WHY? • MORE ISLANDS THERE • ISLANDS WERE CLOSER TO EACH OTHER • MANY S. PACIFIC ISLANDS WERE LARGER • SO…ISLANDS COULD BE BETTER USED FOR NAVAL / AIR BASES • SOUTHERN ROUTE WAS CLOSER TO AUSTRALIA • SO WHAT? • AUSTRALIA WAS ALLIED W/ U.S. • AUSSIE MILITARY WAS VITAL TO VICTORY • MANY U.S. TROOPS WERE BEING TRAINED/SUPPLIED THERE

11. PLANNING THE ADVANCE (cont’d.) • U.S. / ALLIED PLAN TAKES SHAPE: • ALLIED FORCES WILL ADVANCE TOWARD JAPAN ON TWO PARALLEL ROUTES • SOUTH-WEST PACIFIC ROUTE: • SOLOMON ISLANDS – NEW GUINEA – PHILIPPINES • CENTRAL PACIFIC ROUTE: • GILBERT ISLANDS – MARSHALL ISLANDS – MARIANA ISLANDS • WHAT FORCES WILL BE USED?: • S.W. PACIFIC ROUTE: U.S. ARMY, USMC, USN, AUST. • C. PACIFIC ROUTE: USN, USMC • WHO’S IN COMMAND?: • S.W. PACIFIC: DOUGLAS MacARTHUR • C. PACIFIC: CHESTER NIMITZ

13. GUADALCANAL • ALLIED OFFENSIVE BEGINS THERE: WHY? • GUADALCANAL IS @ SOUTHERN END OF JAPANESE EMPIRE • ISLAND HAS AIRFIELD ALLIES NEED FOR FUTURE OPERATIONS • ISLAND CONTROLS SEA LANES TO AUSTRALIA • BOTH SIDES RECOGNIZE IT’S STRATEGIC IMPORTANCE • SO…ALLIES WANT IT / JAPANESE WANT TO KEEP IT • USMC GIVEN INITIAL TASK OF TAKING ISLAND (U.S.ARMY INVOLVED LATER ON) • AUG. ’42-FEB.,’43: VICIOUS FIGHTING ON ISLAND • JAPANESE DESPERATE TO HOLD ISLAND • THE “TOKYO EXPRESS” REINFORCES JAPANESE • U.S. NAVY DISRUPTS “TOKYO EXPRESS” • OTHER PROBLEMS: • TROPICAL CLIMATE • TROPICAL DISEASE (EX. MALARIA) • JUNGLE TERRAIN MAKES MOVEMENT DIFFICULT • FINAL RESULT: • JAPANESE CAN’T MAINTAIN TROOPS / SUPPLIES • CASUALTIES GROW (EX. 22,000 KIA/MIA) • JAPANESE WITHDRAW FROM ISLAND / U.S. CONTROLS ISLAND

17. AERIAL PHOTOGRAPH, HENDERSON AIRFIELD, GUADALCANAL

20. BATTLE MAP,“BLOODY RIDGE”,GUADALCANAL, SEPT., 1942

21. U.S. MARINES ON “BLOODY RIDGE”

22. JAPANESE KIA ON “BLOODY RIDGE”

23. JAPANESE KIA, BLOODY RIDGE, GUADALCANAL, 1942

26. NEW GUINEA • NEW GUINEA: WHY IMPORTANT? • LOCATION • CLOSE TO AUSTRALIA • LOCATED ON IMPORTANT SEA ROUTES TO JAPAN • WAS USED AS A BASE FOR SUPPORTING SMALLER ISLAND GARRISONS • JAPANESE OCCUPIED NORTHERN HALF OF ISLAND • HAD FAILED TO OCCUPY SOUTHERN HALF • WHY? JUNGLE & MOUNTAIN TERRAIN MADE MOVEMENT DIFFICULT • 1942-43: U.S. / AUSSIES DECIDE TO PUSH JAPANESE OFF ISLAND • PROBLEM? • TERRAIN – OWEN STANLEY MTS. ARE DIFFICULT TO PASS • JUNGLE TERRAIN • CLIMATE • DISEASE • SOLUTION? MacARTHUR DECIDES ON SIMPLE PLAN: “OPERATION CARTWHEEL” • BYPASS JAPANESE STRONGHOLDS • USE ARMY & NAVY TO CUT OFF JAPANESE SUPPLIES • STARVE JAPANESE • ONLY ATTACK AREAS THAT ARE VITAL TO ALLIED MOVEMENT • RESULT? • JAPANESE SUFFER MASSIVE LOSSES – 150,000 KIA / MIA • ALLIES SEIZE NEW GUINEA

27. NEW GUINEA

28. THE KOKODA TRAIL,NEW GUINEA, 1942

29. AUSSIES ON THE KOKODA TRAIL, NEW GUINEA, 1942

30. NEW GUINEA U.S. OPERATIONS1942-43

32. AUSTRALIAN ANTI-JAPANESEPROPAGANDA , 1942

33. TARAWA • WHEN? NOVEMBER , 1943 • WHERE? TARAWA ATOLL, GILBERT ISLANDS, CENTRAL PACIFIC • WHAT? JAPANESE-HELD ATOLL W/ AIRFIELD • WHY? • TARAWA WAS THE EASTERNMOST USEABLE AIRSTRIP INSIDE JAPANESE-HELD TERRITORY • CAPTURE WAS VITAL TO ADVANCE TOWARDS JAPAN • ATOLL WAS DEFENDED BY IJN NAVAL INFANTRY W/OUT FLEET SUPPORT • USMC & USN ARE ORDERED TO SEIZE TARAWA & BEGIN USING AIRSTRIP • IJN FORCE: 5000 (approx.) IJN INFANTRY W/ WELL-CONSTRUCTED DEFENSIVE POSITIONS • U.S. FORCE: • USMC 2nd MARINE DIVISION (& ELEMENTS OF USA 27TH INFANTRY DIVISION) • USN – TASK FORCE 30 • TOTAL: APPROX. 35,000 MEN

35. BETIO ISLAND, TARAW ATOLL

36. JAPANESE DEFENSIVE POSITIONS, TARAWA, NOVEMBER, 1943

41. 2nd DIVISION MARINES LAND ON TARAWA

49. PRESENT-ARMS,U.S. MARINES,BETIO, TARAWA,CURRENT-DAY

50. TARAWA (cont’d.) • PROBLEMS: • JAPANESE DEFENSIVE POSITIONS ARE STRONGER THAN ANTICIPATED • NAVAL GUNFIRE IS LESS EFFECTIVE THAN HOPED FOR • AMPHIBIOUS LANDING CRAFT ARE CAUGHT ON CORAL REEF • MARINES ARE FORCED TO WADE ASHORE • CASUALITES ARE VERY HIGH • FINAL CASUALTIES: • IJN: 4900 KIA, APPROX. 200 SURVIVORS • USMC: 3000, APPROX., 900-1000 KIA • SO WHAT? • USN & USMC HAVE TO RE-EVALUATE THEIR AMPHIBIOUS ASSAULT TACTICS • EX.: • HOW CAN NAVAL ARTILLERY BE MADE MORE EFFICIENT DURING THE NEXT ASSAULT? • WHAT ARE THE BEST TACTICS / METHODS TO USE AGAINST JAPANESE POSITIONS? • USN & USMC BEGIN NEW TRAINING METHODS FOR MARINES & NAVAL CREWS