Trump names hostage negotiator as new National Security Adviser

A week after ousting top aide John Bolton, President Donald Trump announced Wednesday on Twitter that he was naming Robert O'Brien to replace Bolton, choosing the State Department's top hostage negotiator to fill that important White House post.

"I have worked long and hard with Robert," the President tweeted from California, where he is currently on a western campaign swing.

"Robert O'Brien is a great choice to be National Security Advisor," said Rep. Mike Gallagher (R-WI), who labeled the choice an 'exceptional pick.'

"He is a high energy, low ego individual who will do fantastic in this role," the Congressman added.

O'Brien's most recent high profile diplomatic effort was in Sweden, where he headlined U.S. efforts to free rapper A$AP.

O'Brien's official title at the State Department was, "Special Presidential Envoy for Hostage Affairs at the U.S. Department of State."

O'Brien will be the fourth National Security Adviser for President Trump, going through former Defense Intelligence Agency chief Michael Flynn, Army General H.R. McMaster, and then Bolton.

Last week, Mr. Trump said Bolton had disagreed with him on a number of major foreign policy issues.