In a way, the black-and-white Palestinian scarf draped over Hannah Sattler’s shoulders this week and the tie-dyed T-shirts of 1968 are woven from a common thread. Like so many college students across the country protesting the Israel-Hamas war, Sattler feels the historic weight of the anti-Vietnam war demonstrations of the 1960s and 70s. “They always talked about the ’68 protest as sort of a North Star,” Sattler, 27, a graduate student of international human rights policy at Columbia University, said of the campus organizers there.