Robert O’Brien was named as one of the Irish Legal 100 in 2018

Robert O’Brien has been named as President Trump’s new National Security Advisor.

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President Trump confirmed the news of his nomination in a tweet on September 18:

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. I have worked long & hard with Robert. He will do a great job!

— Donald J. Trump (@realDonaldTrump) September 18, 2019

O’Brien reportedly interviewed for the position with Trump and acting chief of staff Mick Mulvaney last week in the wake of John Bolton’s departure, which Trump confirmed on Twitter on September 10:

....I asked John for his resignation, which was given to me this morning. I thank John very much for his service. I will be naming a new National Security Advisor next week.

— Donald J. Trump (@realDonaldTrump) September 10, 2019

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O’Brien, who is set to be Trump’s fourth National Security Advisor in three years, most recently served as the Special Presidential Envoy for Hostage Affairs at the US Department of State.

CNN reports that on Tuesday, Trump told reporters on Air Force One: "Robert O'Brien said, 'Trump is the greatest hostage negotiator in history.' He happens to be right.”

"We are 38-0. 38-0, ask Robert. In fact, I had never heard the term. Robert O'Brien said Donald Trump is the greatest hostage negotiator of all time. 38-0. At the time he said it we were 29-0. We are 38-0."

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In 2018, O’Brien, who is a founding partner at Larson O’Brien LLP, was included in the annual Irish Legal 100, which is compiled by IrishCentral’s sister publication Irish Voice newspaper. The Irish American is on the executive board for the Friendly Sons of St. Patrick and is a member of the Irish American Bar Association in Los Angeles.

President Trump has named Irish American Robert O'Brien as his next National Security Advisor.Getty Images