Is it ensure, insure, or assure?
"rapid attack," 1939, from German Blitzkrieg, from Blitz "lightning" (from Middle High German blicze, back-formation from bliczen "to flash," from Old High German blecchazzen "to flash, lighten" (8c.), from Proto-Germanic *blikkatjan, from PIE root *bhel- (1) "to shine, flash, burn;" see bleach (v.)) + Krieg "war" (see kriegspiel).
A form of warfare used by German forces in World War II. In a blitzkrieg, troops in vehicles, such as tanks, made quick surprise strikes with support from airplanes. These tactics resulted in the swift German conquest of France in 1940 (see fall of France). Blitzkrieg is German for “lightning war.”