At the end of 1969 Maj. Gen. Melvin Zais, commanding US XXIV Corps in I Corps, proposed breaking up the 1st Division (with four regiments and about nineteen combat battalions) into two divisions controlled by a "light corps" headquarters responsible for the defense of the Vietnamese Demilitarized Zone (DMZ) area, but his immediate superior, Lt. Gen. Herman Nickerson Jr. (USMC), commanding the III Marine Amphibious Force (and the I Corps senior adviser) and General Hoàng Xuân Lãm, the I Corps commander, both vetoed the idea, citing the lack of enough experienced Vietnamese officers to staff a new command.[1]: 382