What allowed the exponential increase in nuclear warheads in the early 50's?

This remarkable graph from Wikipedia shows quite clearly that in the early to mid 1950’s there was a sudden, and what looks to be exponential, increase in (US) nuclear warheads.

Was the increase due to any particular technological breakthrough? Was it simply that Hydrogen bombs in general were easier to produce than the older fission ones (possibly because the bottleneck of obtaining fissionable uranium or plutonium was less relevant for H-bombs since such material was only required in small quantities - for their initiators and not for the main explosive)? Or, was it that, as usual, mass production leads to gains in efficiency?

Or, indeed, was it simply political, i.e. there was the will and support to manufacture them in such huge quantities?


Pretty sure it had something or everything to do with the Russians getting the bomb. That pretty much was the starting pistol for the arms race that peaked in the late 80’s and still goes on today. So yes it was both a political necessity and some what of a military necessary to build up to keep up with each other. It was MAD.

Mostly a political decision. Eisenhower wanted to decrease the overall size and expense of the armed forces while maintaining a credible defense. So the principle became to reduce conventional forces while having a credible nuclear deterrent.

By about 1955 they had 10 years to validate and perfect the U238 refinement process.
Or was a lot of that plutonium - in which case, they would have built a substantial number of reactors first to create the plutonium?

IIRC the Russians demonstrated their bomb in 1949(?) and the US burst of tech appears to have started about 1956-57. Of course, it also coincides with the development of long-range missiles to supplement the bomber fleet; and I assume, the nuclear sub fleet to also carry nuclear missiles.

That burst of tech you see in 1956 is due to a huge amount of military research and development that happened right after the 1949 event.

From my undergrad PoliSci 1967-1971:

Every target needed X warheads on Y delivery systems - see where this gets nasty with the addition of missiles and subs? X is ALWAYS > 1 to compensate for duds, misses, and enemy defense.

Every time the other side came up with a defense, you needed more firepower to take out the defense. This is (if you want to put on your blinders and say "we would NEVER launch a first strike :rolleyes:) where the “need” for siio-busters came in.

They put another anti-missle battery defending their C&C base #72 (a major strategic target); you need another X warheads on Y delivery systems.

What? They had the audacity to build a system on the same principle?! The bastards! We’ll show them who has the biggest (USSR) and most (US).

The USSR reportedly had developed a 50 megaton monstrosity - one of those at the right altitude just might qualify as a Doomsday device. Don’t know how many they produced or what delivery systems they had for it.

I believe you are referring to the Царь-бомба; “Tsar Bomb”
Developed by the Soviet Union, the bomb had the yield of 50 to 58 megatons of TNT (210 to 240 PJ).

That was the test yield, which validated the design yield of 100 megatons. The one explosion generated approximately 20 percent of all atmospheric nuclear fallout, and the parachute was so large that legend states there was a nylon shortage throughout the Soviet Union for the next 6 months.

Fortunately, there is little practical use for a bomb of that size when the target can be less wastefully destroyed with several smaller bombs (the bomb wasn’t very efficient and used up more nuclear material than several smaller bombs all by itself), not to mention the fact that it could only be carried by a modified Bear bomber, which even in 1961 was a sitting duck.

The US never really went for size, they tested to validate theories. Of course, they had monster explosions as well, but it’s worth noting that the biggest US explosion was completely unexpected and was never approached as far as power output.

It was exponential all the way back to '45 (see the data here). In the first years, there were doublings and even triplings year-to-year, while later on it was more like 50% annual growth.

I’d suppose that while the drivers were political, the actual growth limits were due to technology and infrastructure. The generalized “Moore’s law” is that all technologies show exponential growth in the early days.

My understanding of nuclear weapons design (which, you understand, has been gained mainly by reading Wikipedia articles) is that this isn’t the case. A “hydrogen bomb” will include a “primary” which is a full-scale nuclear fission bomb, which may be “boosted” with a fusion fuel like tritium to increase the efficiency of the fission reaction. (I believe advances in fission weapons design do mean post-World War II fission weapons and/or fission primaries for two-stage weapons are more efficient, allowing more devices to be built with the same amount of uranium or plutonium that were used for the Trinity, Hiroshima, and Nagasaki bombs, but I don’t think that’s the reason for the shape of that curve.) Furthermore, a two-stage thermonuclear weapon (“hydrogen bomb”) will also have a “secondary” which includes a “spark plug” of fissile material (uranium-235 or plutonium-239)–even “thermonuclear” weapons will often still derive the majority of their energy from fission reactions (which may also include fission of natural uranium-238 in the “tamper” of the secondary)–so “hydrogen bombs” will actually require more plutonium or highly enriched uranium, not less, since they use fissile material in both the primary and the secondary (for the sparkplug), along with fusion fuels and un-enriched uranium.

I did not know that (all too obviously).

Thanks (to all).

There is an informative and entertaining book about the history of nuclear weapons, and what can go wrong with them, called Command and Control by Eric Schlosser.

Ask anybody what he wants and the answer is always “more”. Generals are no different.

One thing that happened is that they consistently overestimated (deliberately? Who knows?) the size of the Soviet nuclear arsenal (and there was no need to overestimate the size of their conventional army). One of Kennedy’s main campaign pledges was that he would repair the “missile gap” which in fact didn’t exist. The Russian generals of course were doing the same thing. That a thermonuclear was avoided (so far) can be attributed only to dumb luck.

This is an interesting video showing each nuclear explosion from 1945 to 1998 - A Time-Lapse Map of Every Nuclear Explosion Since 1945 - by Isao Hashimoto - YouTube

Wow, the French surely love to fire off bombs. Looking at their development history, I read this on Wikipedia:

That sounds like the stupidest meeting of the smartest people on earth.

wow that was disturbing. It’s amazing nuclear war never came out of that

The Cold War was a political war. Political wars aren’t determined by actual capabilities but by perceptions. (Assuming they are determined at all. The Cold War wasn’t, really, but both sides were given the impression that they were equal or winning at all times except when more funding was needing, so a final answer wasn’t needed.)

In the press, simple megatonage dominated the discussion. More was obviously better. The U.S.S.R. did bigger better than the U.S. did, as also illustrated by its early much larger rockets and satellites. The U.S. could do more better, though. So we sneakily reversed strategy and fought the propaganda war on that basis. The Russians started working on more as well, for technical reasons given above, and lo, an arms race.

None of them made any necessary sense militarily. (Some of it was sensible, some was not.) Sense was not part of the political conversation, though.

Is it ever?