President Donald Trump’s travel ban faced its toughest test yet Tuesday as a panel of appeals court judges hammered away at the government’s arguments that the ban was motivated by terrorism fears but also directed pointed questions to an attorney who claimed it unconstitutionally targeted Muslims. The contentious hearing before three judges on the San Francisco-based 9th Circuit Court of Appeals focused narrowly on whether a restraining order issued by a lower court should remain in effect while a challenge to the ban proceeds.