OPERATION DOWNFALL CASUALTY ESTIMATES
Chart: 37.5
4m
PERCENT
66.60%
ACTUAL US CASUALTIES AT IWO JIMA AND OKINAWA COMPARED TO ESTIMATED LOSSES FOR OPERATION DOWNFALL PLANNED FOR NOV 1945
65
* Wounded, killed and total casualties shown as a % of US invasion forces
Planned Allied Invasion
Force: 6m
60
US Invasion Force: 180,000
55
98,500
54.70%
50
45
45%
40
35
Planned Allied Invasion Force: 6m
30
28.3% (1.7m)
US Invasion Force: 110,000
25
Planned Allied Invasion Force: 6m
26,017
23.60%
20
20% (1.2m)
17.40%
15
15.50%
10
9.70%
6.20%
5
4.50%
0
% Killed
% Wounded % Casualties
IWO JIMA
19.2.1945 - 26.3.1945
1
2
3
4
5
% Killed
% Wounded % Casualties
OKINAWA
% Killed
% Wounded % Casualties
OPERATION DOWNFALL ESTIMATE
% Killed
% Wounded % Casualties
OPERATION DOWNFALL ESTIMATE
% Killed
% Wounded % Casualties
OPERATION DOWNFALL ESTIMATE
1.4.1945 - 19 June 1945
US Joint Chiefs Estimate
BASE - US Secretary of War Estimate
MAX - US Secretary of War Estimate
The number ofUS troops killed at the Battles of Iwo Jima and Okinawa was 24,300, some 22% of all US troops killed in the Pacific War
US Troops killed in the Pacific War were 110,000 versus 300,000 killed in the war in Europe
Using the US Secretary of War's base estimate, without the atom bomb some 377,000 US troops would have been killed in the Pacific War - significantly exceeding the war in Europe
It should be noted that 1m of the 6m troops earmarked for Operation Downfall were British of whom an estimated 66,000 would have been killed using BASE assumptions as above
The Secretary of War Department estimated 5-10m Japanese civilians killed but at the same ratio as Okinawa (25% Killed) the number would have been 19m civilians killed.
Francis Pike, Hirohito's War, The Pacific War 1941 - 1945 [Bloomsbury 2015]