The University of Michigan has issued a formal apology after a history professor lauded pro-Palestinian student protesters in a commencement speech over the weekend. The remarks — and the ensuing apology — have set off cascading recriminations, with pro-Israel advocates calling to slash the school’s funding as others accuse university officials of bowing to political and donor pressure. In a speech on Saturday at the universitywide commencement ceremony, Derek R. Peterson, a professor of East