At least 20 people were arrested, including a photojournalist, as police and demonstrators violently clashed at the University of Texas at Austin on Wednesday. Hundreds of students walked out of class to protest against the conflict in Gaza and demand the university divest from companies that manufacture machinery used in Israel’s war efforts, carrying signs and chanting. Dozens of local and state police – including some on horseback and holding batons – formed a line to stop protesters from marching through campus. Officers pushed them off the campus lawn and at one point sent people tumbling into the street. According...