 Complete the following phrase:  A little-known role of the P-38 in the European theater was that of fighter-bomber during the invasion of Normandy and the Allied advance across France into Germany. Assigned to the IX Tactical Air Command, the 370th Fighter Group and 474th Fighter Group and their P-38s initially flew missions from England, dive-bombing radar installations, enemy armor, troop concentrations, and flak towers, and providing air cover. The 370ths group commander Howard F. Nichols and a squadron of his P-38 Lightnings attacked Field Marshal Günther von Kluges headquarters in July 1944; Nichols himself skipped a bomb through the front door. The 370th later operated from Cardonville, France, and the 474th from various bases in France, flying ground-attack missions against gun emplacements, troops, supply dumps, and tanks near Saint-Lô in July and in the 