A mob of Columbia University and Barnard College radicals stormed a campus library Wednesday afternoon, just one week after they took over another Barnard building and sent a security guard to the hospital. Video footage shows droves of masked radicals clad in dark clothing storming Barnard's Milstein Library through a back exit that an accomplice held open. Columbia University Apartheid Divest (CUAD) and Columbia Students for Justice in Palestine (SJP)—the Ivy League institution's most anti-