Good episode in a well-done series.
The narrator claims that Mikhael Kalashnikov's AK-47 assault rifle is the most important weapon of the 20th century and it's hard to argue against the claim, if for no other reason than that so many were produced and they are no ubiquitous, found in the hands of both friend and foe.
World War II began with rifles that would have been fine for World War I. An infantryman's rifle fires a powerful bullet that's accurate at long range. If you want to hit a target two football fields away, that's your weapon. All the rifles of World War II were long range and accurate.
But leaders found that long-range accuracy was less often necessary than it was when soldiers were shooting at one another from trenches. World War II was a war of movement and brought enemies closer together, sometimes in urban rubble. Each nation had its own version of a machine pistol that fired automatically, but they fired pistol rounds and were inaccurate.
The assault rifle filled the gap between the submachine gun and long-range rifle. It fired high-velocity rounds on either semi-automatic (one shot per trigger pull) or fully automatic (continuous fire as long as the trigger is held down).
Can I make an editorial note? (Of course I can.) There is a rather fierce debate going on these days in the USA about banning "assautl rifles." I don't get the impression that more than half the people arguing about it know what an assault rifle is, technically. Fully automatic weapons are already banned, except by special permission. I've seen photos of "assault rifles" that should be banned and as far as I can determine they are all perfectly legal semi-automatics. What they have in common is that they are all "ugly guns" that resemble something that might be found in an Arnold Schwarzenegge action movie.
Back to the program. Kalashnikov is shown in a recent interview, when he was almost eighty. He's proud of his invention and is able to joke with American interviewers about how the American M-16 used a smaller round and was still effective, so the AK-47 was retooled for a smaller round too.
A note on what sociologists call the social construction of reality. In the late 1950s I, who knew little about guns, was chatting with an enthusiast who did. The Soviet's AK-47, he pronounced, was a piece of junk, so poorly made by peasants that the parts rattled when the rifle was carried. I gather it's now widely accepted that the greater tolerance in the manufacture of the gun was deliberate. At least that's what Kalashnikov says. The result was a weapon in which the parts were loose and rattled but, being less tightly machined, could survive all manner of abuse and still work properly.
An American Vietnam veteran described picking up at AK-47 and storing it in his locker. Some months later he retrieved it and found it had rusted shut. He had to kick the bolt open with his boot. And on the range, it worked as well as ever. Anecdotes from elsewhere have them firing properly after being frozen and thawed, filled with sand or mud, and so forth. It's been modernized over time and our troops are still facing AK-47s some sixty years after its adoption by the USSR.