WASHINGTON: US President Donald Trump on Wednesday named his pointman for hostage situations, Robert O´Brien, to replace his hawkish national security advisor sacked last week. “I have worked long & hard with Robert. He will do a great job!” Trump tweeted Last week, Trump abruptly fired John Bolton, a vigorous proponent of using US military force abroad and one of the main hawks in the administration on Iran. O´Brien has until now served as Trump´s envoy for situations involving US hostages abroad. He comes into the new job with backing from Secretary of State Mike Pompeo and senior Republicans in Congress. Bolton, by contrast, was a highly controversial figure in Washington.