WASHINGTON (Reuters) - Conservative U.S. Supreme Court justices on Wednesday signaled they are likely to uphold President Donald Trump’s travel ban on people from several Muslim-majority countries, one of the most contentious policies of his presidency. Both Chief Justice John Roberts and Justice Anthony Kennedy, a frequent swing vote on the nine-justice court, indicated they were unwilling to second-guess the president on the national security justifications for the policy. The challengers led by the state of Hawaii have argued the policy was motivated by Trump’s enmity toward Muslims and that it violates federal immigration law and the U.S.