I think they use the Singlepoint for the Son Tay Raid. It had a 16 MOA.. Great start for the red-dot industry,, by not practical for most hunters and mother Army.
A friend had one in the 70t's. If you used it for any period of time your eyes get blurry.
The US was way behind the curve on optics.
The Brit/IDF SUIT (sight unit infantry trilux) was a superior 4x scope, but still not a night vision product. The same with the German Hensoldt Z24.