A protester holds up a sign at a protest on Columbia's campus. Demonstrators are demanding the school divest from Israel.Alex Kent; Getty ImagesProtests have rocked Columbia University's campus.Demonstrators opposing the war in Gaza want the school to divest from Israel.In 1985, protesters had staged their divestment campaign — and it worked.The unrest at Columbia University isn't showing signs of slowing down.Student protests are escalating there and other college campuses over the Israel-Gaza war and schools' investments in Israeli entities, with demonstrators on Tuesday breaking into a Columbia campus building and occupying it.It's a shockingly familiar scene.In the 1980s, student protesters at Columbia took over the same building and called for divestment of the Ivy League school's investments over a different cause: South African apartheid.But while that movement was a success, protesters today may find it harder to push the school into divesting.Protests over Israel's war in Gaza rageStudent demonstrators are calling for the Ivy League institution to divest from Israel and accuse the Jewish nation of killing civilians in Gaza.The protesters are specifically demanding the school sell off investments not just from Israeli companies but from those that have ties to Israel, including engineering firms Lockheed Martin and Boeing and tech giants like Alphabet and Amazon, according to NPR.Students have also called on the school to boycott Israeli universities and institutions, protect pro-Palestinian students and faculty, and make a statement condemning the war in Gaza.The protesters swarmed the campus and set up tents.