Explosive Power Beats Even Moore’s Law

The power of destructiveness is the most impressive metric of modern technology

2 min read
A photo of a nuclear explosion with islands in the foreground.

On 30 October 1961, the Soviet Union detonated the Tsar Bomba hydrogen bomb, which had the destructive power of 50 megatons of TNT, or 210 petajoules.


The rising number of components on a microchip is the go-to example of roaring innovation. Intel’s first microprocessor, the 4004, released in 1971, had 2,300 transistors; half a century later the highest count surpasses 50 billion, for the Apple M1 Max—an increase of seven orders of magnitude. Most other technical advances have lagged behind: During the entire 20th century, maximum travel speeds rose less than tenfold, from about 100 kilometers per hour for express trains to 900 km/h for cruising jetliners. Skyscrapers got only 2.4 times as tall, from the Singer Building (187 meters) to the Petronas Towers (452 meters).

But there is one accomplishment that, unfortunately, has seen even higher gains since 1945: the destructive power of explosives.

Modern explosives date to the 19th century, with trinitrotoluene ( TNT) and dynamite in the 1860s, followed by RDX (Royal Demolition Explosive), patented in 1898. During the Second World War, explosive power rained on European and Japanese cities in the form of mass-scale bombing, and by the war’s end, in 1945, the most powerful explosive weapon was the Nazi V-2 rocket. It carried 910 kilograms of amatol—a blend of TNT and ammonium nitrate—and had an explosive energy of about 3.5 gigajoules.

The increase in explosive power, over 16 years, matches what Moore’s Law has accomplished in the 50 years since 1970

And then came an entirely new class of explosives, those exploiting nuclear fission and fusion. The bomb that exploded over Hiroshima on 7 August 1945 released 63 GJ of energy, half of it as the blast wave, about a third as thermal radiation. The Nagasaki bomb, dropped two days later, released about 105 GJ. But these first two bombs were tiny when compared to what came later. The most powerful U.S. hydrogen (or fusion) bomb, tested in 1954, was equivalent to 15 megatons of TNT (63 petajoules). This was far surpassed on 30 October 1961, when the Soviet Union tested the RDS-220 bomb above Novaya Zemlya in the Arctic Ocean. Fifty-nine years later, in August 2020, Rosatom (Russia’s atomic energy agency) released a 40-minute-long film that claimed that the bomb, nicknamed the tsar bomba—the emperor’s bomb—had had a yield of 50 megatons.

In this remarkable video, the antiquated analog instrumentation provides a strange contrast with the weapon’s immense destructive power. The bomb—hung beneath the belly of a Tu-95 bomber—was dropped by parachute from a height of 10.5 kilometers and detonated 4 km above the ground. The explosion released 210 PJ of energy, three orders of magnitude more than the Nagasaki bomb, creating a mushroom cloud of 60-65 km in diameter and a flash visible from nearly 1,000 km away. And soon afterward Nikita Khrushchev, the Soviet premier, claimed that his country had built but not tested a bomb twice as powerful.

The last V-2 attack on London came on 27 March 1945, less than six weeks before the Nazi surrender. By the Novaya Zemlya test in 1961, the maximum explosive energy of weapons had risen by seven orders of magnitude, to more than 200 PJ. That increase, over 16 years, matches what Moore’s Law has accomplished in the 50 years since 1970. It is a reminder of the terrible priorities of modern civilization.

This article appears in the July 2022 print issue as “A Moore’s Law—for Bombs.”

The Conversation (5)
Wayne Craig15 Jul, 2022

i would like to present a theory about the image above of the hydrogen bomb, the round clouds are most likely to be that of water vapour that's created by the hydrogen bomb.

Frank Schaedlich07 Jul, 2022

There are a couple of glaring numerical errors in this article. How can a V2 (approx. 1 ton of TNT) produce 3.5 GJ of energy while the Hiroshima bomb (approx. 15 kilotons of TNT) produce an energy of 63 GJ, only eighteen times greater?

The Hiroshima yield, and the Nagasaki yield are TJ, not GJ.

Keith Lofstrom30 Jun, 2022

Moore's law replaced nuclear weapon yield with targeting accuracy. The Tsar Bombe did more economic and physical damage to the USSR than it could ever do to an enemy, especially an enemy with electronically-enabled defenses. That monster and its enormous delivery system would be an easy interception target today. Showy; strategically useless.

Today's 100kT class weapons are frightening because they are small and cheap - a few automation hours per warhead. Efficient implosion, small electronic packages, pea-sized detonators connected by fiber optics, system-optimized by super-computing (enabled by Moore's law).

A 100kT nuke delivered EXACTLY can destroy a hardened missile silo more effectively than a 20MT nuke mis-delivered 10 km away.

OTOH, one GOOD (?!) thing is that our hundreds of billions of Moore's-Law-enabled consumer devices consume near-terawatt levels of grid power. Some of that grid power is nuclear, and some of the reactor fuel is reprocessed weapon fuel. About 10% of the energy my chips use was originally Pu-239 or enriched U-235 in US and Russian weapons cores designed to kill millions, including me.

Perhaps Moore's law will someday enable swarms of AI micro-robot weapons, drilling into our brains or hearts and disrupting neural functions that keep us alive. Chip designers may become the next Robert Oppenheimers.

This isn't a question of biggest numbers, it is about wisely applying those numbers. Not how fast we grow, but WHY???

How the Graphical User Interface Was Invented

Three decades of UI research came together in the mice, windows, and icons used today

18 min read
Stylized drawing of a desktop computer with mouse and keyboard, on the screen are windows, Icons, and menus
Getty Images/IEEE Spectrum

Mice, windows, icons, and menus: these are the ingredients of computer interfaces designed to be easy to grasp, simplicity itself to use, and straightforward to describe. The mouse is a pointer. Windows divide up the screen. Icons symbolize application programs and data. Menus list choices of action.

But the development of today’s graphical user interface was anything but simple. It took some 30 years of effort by engineers and computer scientists in universities, government laboratories, and corporate research groups, piggybacking on each other’s work, trying new ideas, repeating each other’s mistakes.

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