The direct translation from German is "lightning war." In practice, it meant a rapid assault by an overwhelming force.
Assault is a noun (an assault) and a verb (to assault).
No, assault does not need to be capitalised.
German Stg 44, IIRC
Battle of the Somme.
the somme
An assault on tradition. Many assault attacks are described in history. The terrorists made an assault attack on the kingdom
the weather did the trick
The police intervened at the right time and stopped the assault.
Chre is not a German word
Sturmmann (literally "assault man" but usually translated as Stormtrooper)
The German FG42 was the first true assault rifle.