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> Especially since those early ICBMs were so inaccurate that they would have been completely pointless if armed with 1945-era bombs. It took the development of

> Especially since those early ICBMs were so inaccurate that they would have been completely pointless if armed with 1945-era bombs. It took the development of multi-megaton thermonuclear weapons for those early ICBMs to be useful weapons. The Atlas had a CEP of 1.4km, which was good enough for a kiloton-class warhead. Plus, its original warhead was only 1.44Mt. It was mostly lack of priority that delayed the first operational squadron to 1959.

CapitalistCartr 10y ago
20kt at 1400 meters won't yield 6 psi overpressure. And "only 1.4 megatons"??? That's two orders of magnitude larger than Hiroshima. It took many tests and advancements to go from a fission release to a fission-fusion weapon.
- vonmoltke 10y ago
  Little Boy, with an effective yield of ~15kt, had a 5psi radius of 3500m. The "only" in my comment was a response to the assertion that it required "multi-megaton" warheads to make ICBMs practical.
  - CapitalistCartr 10y ago
    We never had many megaton weapons. Two megaton was about the limit, and most weapons were under 500 kilotons. Accuracy is better. Huge bombs was a dick-waving contest, and after Tsar Bomba, we gave up that game and went for sophistication.
    - mikeash 10y ago
      The W38 used on Atlas and Titan 1 was 3.75 megatons. If we consider bomber weapons, the B41 was a 25 megaton weapon with about 500 built. The B53/W53 was a 9 megaton bomb for both bombers and missiles, with around 100 built. There are more beyond 2 megatons; these are examples, not a comprehensive list. Huge bombs weren't a dick-waving contest, they were partly to maximize the value of an ICBM carrying one warhead, and partly to mitigate inaccuracy. As MIRV became practical and accuracy increased, yields decreased on both sides of the Cold War, because smaller bombs are just plain more efficient if you can put them where they need to go.
    - arethuza 10y ago
      The Soviets and then the Russians deployed variants of the SS-18 with very large warheads (20-25Mt) until fairly recently - either for EMP purposes or to attack Cheyenne Mountain, Raven Rock Mountain etc. https://en.wikipedia.org/wiki/R-36_(missile) https://en.wikipedia.org/wiki/R-36_(missile)
    - hga 10y ago
      They're useful for very hard targets, like dropping two 20Mt or so at the same time at each end of the access tunnel for the Cheyenne Mountain Complex (https://en.wikipedia.org/wiki/Cheyenne_Mountain_Complex https://en.wikipedia.org/wiki/Cheyenne_Mountain_Complex). Otherwise, at something in the 1 Mt plus or minus level, I forget, a lot of the energy is wasted by being thermally re-radiated out into space.
  - mikeash 10y ago
    Are you sure about that? The NUKEMAP[0] shows a 15kt airburst with a 5psi radius of 1.67km. And "most residential buildings collapse" isn't going to be very useful against military targets, there I think you're looking more at the 20psi level, which is only 340 meters. [0] http://nuclearsecrecy.com/nukemap/ http://nuclearsecrecy.com/nukemap/
    - vonmoltke 10y ago
      It looks like I was going off bad information. I ran the numbers (as best I could) in the Nuclear Bomb Effects Computer[1] and I'm getting a radius of about 1mi. The Wiki author claims to have run the same calculation with the same computer and come up with 2.2mi, though he later contradicts himself by saying the 5 psi contour at Hiroshima was at 1.1mi. [1] http://www.fourmilab.ch/cgi-bin/Bombcalc?yield=15&yunit=1&range=1&runit=1&rotate=0&imsize=800 http://www.fourmilab.ch/cgi-bin/Bombcalc?yield=15&yunit=1&ra...
      - mikeash 10y ago
        1 mile fits with the NUKEMAP number of 1.67km, so it seems reasonable to go with that unless there's something better. 2.2 versus 1.1 smells like mixing up radius with diameter, but I could be completely wrong about that.
hga 10y ago
Not if your doctrine is counter-force, which was our doctrine until the utterly evil Robert Strange McNamera (https://en.wikipedia.org/wiki/Robert_McNamara https://en.wikipedia.org/wiki/Robert_McNamara see also what he did with Vietnam and then destroying 3rd World agriculture while heading the World Bank (the Edsel, on the other hand, may be something he did the right thing in canning)) changed it to counter-value (https://en.wikipedia.org/wiki/Countervalue https://en.wikipedia.org/wiki/Countervalue). After that, it wasn't difficult for the Soviets to convince themselves and their military, people, etc. that we were evil, for we very much were.

CapitalistCartr 10y ago

20kt at 1400 meters won't yield 6 psi overpressure. And "only 1.4 megatons"??? That's two orders of magnitude larger than Hiroshima. It took many tests and advancements to go from a fission release to a fission-fusion weapon.

vonmoltke 10y ago
Little Boy, with an effective yield of ~15kt, had a 5psi radius of 3500m. The "only" in my comment was a response to the assertion that it required "multi-megaton" warheads to make ICBMs practical.
- CapitalistCartr 10y ago
  We never had many megaton weapons. Two megaton was about the limit, and most weapons were under 500 kilotons. Accuracy is better. Huge bombs was a dick-waving contest, and after Tsar Bomba, we gave up that game and went for sophistication.
  - mikeash 10y ago
    The W38 used on Atlas and Titan 1 was 3.75 megatons. If we consider bomber weapons, the B41 was a 25 megaton weapon with about 500 built. The B53/W53 was a 9 megaton bomb for both bombers and missiles, with around 100 built. There are more beyond 2 megatons; these are examples, not a comprehensive list. Huge bombs weren't a dick-waving contest, they were partly to maximize the value of an ICBM carrying one warhead, and partly to mitigate inaccuracy. As MIRV became practical and accuracy increased, yields decreased on both sides of the Cold War, because smaller bombs are just plain more efficient if you can put them where they need to go.
  - arethuza 10y ago
    The Soviets and then the Russians deployed variants of the SS-18 with very large warheads (20-25Mt) until fairly recently - either for EMP purposes or to attack Cheyenne Mountain, Raven Rock Mountain etc. https://en.wikipedia.org/wiki/R-36_(missile) https://en.wikipedia.org/wiki/R-36_(missile)
  - hga 10y ago
    They're useful for very hard targets, like dropping two 20Mt or so at the same time at each end of the access tunnel for the Cheyenne Mountain Complex (https://en.wikipedia.org/wiki/Cheyenne_Mountain_Complex https://en.wikipedia.org/wiki/Cheyenne_Mountain_Complex). Otherwise, at something in the 1 Mt plus or minus level, I forget, a lot of the energy is wasted by being thermally re-radiated out into space.
- mikeash 10y ago
  Are you sure about that? The NUKEMAP[0] shows a 15kt airburst with a 5psi radius of 1.67km. And "most residential buildings collapse" isn't going to be very useful against military targets, there I think you're looking more at the 20psi level, which is only 340 meters. [0] http://nuclearsecrecy.com/nukemap/ http://nuclearsecrecy.com/nukemap/
  - vonmoltke 10y ago
    It looks like I was going off bad information. I ran the numbers (as best I could) in the Nuclear Bomb Effects Computer[1] and I'm getting a radius of about 1mi. The Wiki author claims to have run the same calculation with the same computer and come up with 2.2mi, though he later contradicts himself by saying the 5 psi contour at Hiroshima was at 1.1mi. [1] http://www.fourmilab.ch/cgi-bin/Bombcalc?yield=15&yunit=1&range=1&runit=1&rotate=0&imsize=800 http://www.fourmilab.ch/cgi-bin/Bombcalc?yield=15&yunit=1&ra...
    - mikeash 10y ago
      1 mile fits with the NUKEMAP number of 1.67km, so it seems reasonable to go with that unless there's something better. 2.2 versus 1.1 smells like mixing up radius with diameter, but I could be completely wrong about that.

hga 10y ago

Not if your doctrine is counter-force, which was our doctrine until the utterly evil Robert Strange McNamera (https://en.wikipedia.org/wiki/Robert_McNamara https://en.wikipedia.org/wiki/Robert_McNamara see also what he did with Vietnam and then destroying 3rd World agriculture while heading the World Bank (the Edsel, on the other hand, may be something he did the right thing in canning)) changed it to counter-value (https://en.wikipedia.org/wiki/Countervalue https://en.wikipedia.org/wiki/Countervalue). After that, it wasn't difficult for the Soviets to convince themselves and their military, people, etc. that we were evil, for we very much were.