A storm trooper is a member of storm troops, also called shock troops, which are trained for sudden assaults. They carried out attacks in World War I and in World War II, and they were a politica militia of the Nazi party (see Sturmabteilung or Brownshirts). The English storm troops is a direct translation of the German Sturmtruppen.
https://www.dictionary.com/browse/storm-trooper
They were called storm troopers because they were the ones who stormed trenches during an assault.
It wasn’t considered a bad thing then, they were considered the elite.
Yeah, it is.
But I don’t know what to tell you, the term predates the nazis by quote a bit.
They adopted it, but it was known from the age of dragoons: https://en.wikipedia.org/wiki/Shock_troops
The sacred band of thebes were considered shock troops, and I’d suggest that’s closer to what the Russian idiots meant.
But I also wouldn’t be surprised if they were just copying the nazis without knowing.