'Oppenheimer' the movie versus our nuclear reality

Seventy-eight years ago, the first atomic bombs fell on Hiroshima on Aug. 6, 1945, and Nagasaki on Aug. 9, 1945. About 200,000 Japanese were initially killed. 

The summer blockbuster “Oppenheimer” tells this story from the perspective of J. Robert Oppenheimer, the technical director of the Manhattan Project at Los Alamos, New Mexico, that built the bomb. But the movie does not tell the whole story, depriving the public of a broader understanding of the impact of the arrival of the nuclear age.

The movie omits how and why the actual decision to use these weapons was made and, despite Oppenheimer’s great regret about becoming a “destroyer of civilization,” that would become relevant only after the first hydrogen bomb was detonated in 1952.

The White House meeting to use these weapons lasted about an hour. The alternative was to continue the war and invade the Japanese home islands. But Operation Downfall, the invasion plan, estimated at least a million Allied casualties and many times that for the Japanese given their history of suicidal resistance. Hence, there was little debate on dropping the bombs.

After the “Little Boy” bomb leveled Hiroshima, the Japanese war cabinet voted to continue fighting. But when “Fat Man” destroyed Nagasaki, home to Japan’s largest Christian population and about 400 prisoners of war, the war cabinet was deadlocked. The emperor broke the deadlock. Japan would surrender unconditionally. The reason was “shock and awe.”

People could understand how thousands of plane bombing raids could cause vast amounts of death and destruction. But one bomb from a single bomber creating that carnage was inconceivable. The Japanese also did not know how many atomic weapons the U.S. possessed and assumed the worst. Hence, from suicidal resistance, Japan was shocked and awed into total capitulation.

The damages from the atomic bombings and Japanese deaths were expected to be no greater than the firebombing raids on Japanese and German cities. Tokyo and Nagoya,  Hamburg, Dresden and Berlin had been continuously firebombed. The Japanese battleship “Haruna” was also firebombed. Hundreds of thousands of civilians died in those incidents, perishing in infernos as deadly as those caused by the atom bombs, many more than were initially killed at Hiroshima and Nagasaki.

Enola Gay was the single B-29 that bombed Hiroshima. The nuclear bombs dropped on Hiroshima and Nagasaki were in the 20 kiloton range. One kiloton had the explosive equivalent of 1,000 tons of TNT. Hence, the two atom bombs each had the power of 40,000 tons of TNT and were generated by nuclear fission — that was splitting atoms using uranium-235 and plutonium-239.

Then, nuclear weapons were seen as more powerful extensions of conventional weapons requiring fewer delivery systems. The future debate over the 1949 U.S. defense budget and the supercarrier versus the B-36 largely rested on the assumption that nuclear weapons were not existential to society. 

But the thermonuclear age changed the nature of war, confirming Oppenheimer’s worst fears. For the only time in history, war was existential. In a thermonuclear war, assuming the combatants maintained a so-called “second strike” capability to retaliate fully if hit first, there would be no winners — only losers. And “boosted” fission would greatly increase the power of nuclear weapons.

A thermonuclear weapon is based on fusing atoms. The power of the first hydrogen bomb was about 10 megatons. A megaton is the equivalent of 1 million tons of TNT, or potentially, 1,000 times larger than a nuclear weapon.

B-29s could carry a 20-ton payload. Two thousand B-29s carried the combined explosive power of one 20 kiloton A-bomb. But a 20 megaton hydrogen bomb would have required 2 million B-29s to impose the same level of damage.

Whether or not Oppenheimer had the foresight to recognize the consequences of thermonuclear war, he certainly opposed developing those weapons. However, the nuclear genie was long out of the bottle. If the U.S. had not proceeded, the Soviet Union almost certainly would have, as Moscow had stolen many of our nuclear secrets, of which the “super bomb” was one.

But the question that Oppenheimer posed about weapons threatening humanity is more relevant today. Unlike the Cold War, China no longer believes, as Mao did, that “to have a few [atom bombs] is just fine.” Along with the U.S. and Russia, there could be three nuclear superpowers.

Britain, France and North Korea likewise are nuclear-armed as is Israel, which still has not confirmed its status. A number of states could go nuclear, including Japan, South Korea, Taiwan and, to the dismay of the U.S. among others, Iran. 

What can be done to prevent armageddon? That may be the looming strategic question of the coming decades.

Harlan K. Ullman, Ph.D. is a senior advisor at Washington, D.C.’s Atlantic Council and the prime author of the “shock and awe” military doctrine. His 12 book, “The Fifth Horseman and the New MAD: How Massive Attacks of Disruption Became the Looming Existential Danger to a Divided Nation and the World at Large,” is available on Amazon. He can be reached on Twitter @harlankullman.