The attack on Khe Sanh, which began on 21 January before the other offensives, probably served two purposes—as a real attempt to seize the position or as a diversion to draw American attention and forces away from the population centers in the lowlands, a deception that was "both plausible and easy to orchestrate." In Westmoreland's view, the purpose of the base was to provoke the North Vietnamese into a focused and prolonged confrontation in a confined geographic area, one which would allow the application of massive U.S. artillery and air strikes that would inflict heavy casualties in a relatively unpopulated region. By the end of 1967, MACV had moved nearly half of its manoeuvre battalions to I Corps in anticipation of just such a battle.