Harvard University has sued US President Donald Trump's administration over the decision to revoke the Ivy League school's ability to enrol international students. In a complaint filed in Boston federal court, Harvard called the revocation a "blatant violation" of the US Constitution's First Amendment and other federal laws. It also said the revocation had an "immediate and devastating effect" on the university and more than 7,000 visa holders. "With the stroke of a pen, the government has sought to erase a quarter of Harvard's student body, international students who contribute significantly to the University and its mission," Harvard said. "It...