In 1966 and 1967, the U. S. forces in Vietnam increased their activity, launching many search and destroy missions, including Operation Masher/Whitewing and Operation Junction City. But as the US casualty count and the economic cost of the war rapidly increased, opposition to the war within the U. S. also grew. Meanwhile, in late 1967, the North Vietnamese Army began planning a major offensive that would consist of attacks all over South Vietnam and would hopefully deal a knockout blow to the ARVN and the government of South Vietnam.