Dozens of pro-Palestinian protesters at Columbia University were arrested Thursday afternoon and an on-campus tent encampment was removed after the school's president gave the New York Police Department the green light to clear the protesters. Columbia President Nemat &;quot;Minouche&;quot; Shafik announced in a letter to the Columbia community Thursday that she has authorized the New York Police Department to clear demonstrators from campus‚ writing‚ &;quot;This morning‚ I had to make a decision that I hoped...