The Vietnam antiwar movement moved along mutually supportive paths; one within the formal political system and one outside. Dissent within the government expanded over time. Distinct elements of the outsider movement exerted greater influence at different points. Liberal reformers dominated until 1967 and after mid-1971, and intermittently during election campaigns and the fall 1969 Moratorium. Leftists were most evident during major coalition events of 1967 through the May Day demonstrations of spring 1971. Massive student protests in both 1968 and 1970 were ideologically ambiguous. Drawing encouragement and political leverage from the “outsider” movement, federal and state legislators and officials in the executive branch played their most significant role in collaboration with the activist core after 1971.