Did America have to unleash the A-bomb to end the war?

The napalm bombing of more than 60 Japanese cities remains far less notorious than the atomic attacks on Hiroshima and Nagasaki, even though more people died. So why did America decide to use the ultimate weapon?

- By Iain MacGregor

INTHE final months of the Second World War, the XX Bomber Command of the United States Army Air Force (USAAF), based 1,500 miles to the south east on the Mariana Islands, unleashed an intense aerial bombardment over Japan.

Their air campaign would be initially applied through conventional high explosive raids, before strategists opted for indiscriminate firebombing raids and, ultimately, with the deployment of atomic bombs on Hiroshima and Nagasaki.

While historians continue to debate the necessity and morality of the atomic bombings, a critical question remains: could the firebombing campaign alone have forced Japan to surrender, or were the atomic bombs essential to ending the war?

Through three years of study for my latest book, conducting archival research and interviews with eyewitnesses on both sides, I considered the scale of destruction, human cost, military strategy and political context that shaped the final decisions of 1945.

Between 1942 and 1944, American chemists developed one of their deadliest weapons: napalm a highly-flammable gel-like incendiary substance that would stick to surfaces and burn intensely, thus causing widespread fire damage and severe injuries on its target. Though it later found notoriety in the Vietnam War, entering the public consciousness in dozens of war movies, it was first used in industrial quantities against Japan in the spring of 1945. The country's traditional architecture constructed of wood and paper was ripe for such an offensive and the firebombing of Japanese cities, especially Tokyo, would reach unprecedented levels of devastation.

On the night of March 9-10, 1945, in an operation codenamed "Meetinghouse", some 330 American B-29 bombers of the XX Bomber Command led by General Curtis LeMay dropped nearly 1,700 tons of incendiary bombs on densely populated wooden neighbourhoods of Tokyo.