A lawyer by trade, former Bush delegate at the UN, and campaign advisor to Mitt Romney and Scott Walker, O’Brien has been serving as special envoy for hostage affairs.
President Trump has named Robert O’Brien, the current top U.S. hostage negotiator, to be his fourth national security advisor.
“I am pleased to announce that I will name Robert C. O’Brien, currently serving as the very successful Special Presidential Envoy for Hostage Affairs at the State Department, as our new National Security Advisor,” Trump wrote in a tweet Wednesday morning. “I have worked long & hard with Robert. He will do a great job!”
Trump fired John Bolton, his previous national security advisor, in a tweet last week, following months of reports that he had fallen out with his more hawkish advisor. His first national security advisor, Michael Flynn, resigned over revelations that he had misled the vice president about his communications with the Russian ambassador.
O’Brien, a lawyer by trade, served as a UN delegate under President George W. Bush. In the early days of the Trump administration, he was considered for the Navy Secretary job before taking on the hostage negotiator role.
In 2015, Defense One profiled O'Brien, who was then advising Gov. Scott Walker's early bid for the presidency. O'Brien previously had worked for Mitt Romney's campaigns and failed to convince him to run a third time in 2016. The article described how O'Brien had split from his law partner and fellow Romney advisor Pierre-Richard Prosper, who was backing establishment candidate Jeb Bush, as an example of a perceived split among Republican foreign policy wings.
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Although O’Brien has largely flown under the public radar, he caught some attention in July when the president controversially dispatched him to Stockholm to “support” the U.S. rapper A$AP Rocky in an assault trial there.
Rumors that Bolton was on the way out had circulated in Washington for months before his dismissal. Although Bolton and Trump shared a disdain for multilateralism, Bolton often clashed with his boss’ noninterventionalist instincts.
O’Brien is a less-known quantity than Bolton, who served in the Reagan and both Bush administrations, was a regular commentator on Fox News, and wrote several high-profile opinion piece for the Wall Street Journal.