In ground , penetration is the breaching of, and moving past, a defensive military line. Penetration is a strategic military maneuver much like the pincer movement with a few differences. The penetration attack goes straight through the enemy's lines and, once through, each flank turns and attacks the opponent's rear, similar to the blitzkrieg strategy. Flank attack and other forms of maneuver are preferred to the penetration or frontal attack.