With less than a week to go until the centennial celebration, Dwayne Day has an interesting bit of space history about Robert Heinlein over at The Space Review.

There's a wee bit of extrapolation from a single 1945 memo written by Heinlein to characterize Heinlein's beliefs over his lifetime. My take is that he's wrong here (he stated in that memo that conventional military systems were obseleted by the atomic bomb) not because of his biases, but because the scenario of atomic bombs getting used frequently didn't happen. In other words, being wrong and being biased aren't the same thing. Even if things had played out exactly like he said, he'd still be biased.

I think it's unfair for the author to then extrapolate from this single memo to claim

That is worth considering today, six decades later, when Heinlein is still held in such high esteem as a prophet for the NewSpace movement.

In other words, he made a boldly wrong prediction 60 years ago so we should be careful about what he said. Perhaps the author is uncomfortable with the level of idolation that Heinlein currently receives? I don't know. But it seems a peculiar caution to make. After all, the most common characteristic of predictions is that they are wrong.

I would also point out that the bomb Heinlein was familiar with in 1945 was not the one that made atomic war so unpalatable.

A fission warhead does not do the same scale of damage as the subsequent fusion weapons have demonstrated. I would argue that nuclear war only became unthinkable when the blast radius jumped from 5 miles to 50 miles.

That, along with mass warhead production and MIRV technology, made the total destruction of nations possible, and subsequent nuclear war unpalatable.

Don't forget that in the early years after 1945, nukes were seen as little more than "really big bombs". The stigma and fear of using them came much later.

Heck, ISTR that it was proposed to use 9 of them ahead of the landings on Japan. Of course, we didn't fully understand the persistence and effects of radiation until Japan surrendered and we got to see Hiroshima up close.

That, along with mass warhead production and MIRV technology

The significant effects of thermonuclear weapon technology was not that the bombs became much bigger -- they can make fission bombs with megaton yield as well, although there are safety issues, and big bombs are inherently inefficient at causing damage, per unit of yield -- but that it made bombs of a given yield lighter and usually cheaper.

I think Heinlein's view of atomic weapons was also influenced by his own pre-WW2 fiction work: He had thought about atomic-based weapons (though not explosives) as far back as 1939 - 1940. The result was his story 'Solution Unsatisfactory,' in which the concept of 'mutual assured destruction' and the necessity of a super-national peacekeeping force were major points.