Trump said Bolton’s appointment will be effective on April 9.
In an interview with Fox News shortly after Trump tweeted, Bolton said his appointment wasn’t finalized until Thursday afternoon. “I didn’t expect an announcement this afternoon, but it’s obviously a great honor.”
Bolton, once rumored to be Trump’s pick for secretary of state or top choice to run day-to-day operations at the State Department, is considered one of the world’s most disliked foreign policy operators. During his less than two years serving as the U.N. ambassador under former President George W. Bush, there was a severe uptick in anti-American sentiment among diplomats.
Bolton also served in the State Department under presidents George H. W. Bush and Ronald Reagan.
The new national security adviser may push for aggressive stances toward Russia, the self-described Islamic State group and North Korea, experts familiar with his track record say. In a Wall Street Journal op-ed published last month, Bolton argued there is a legal case for a U.S. strike against Pyongyang.
He has stood by the 2003 decision to invade Iraq, even as bipartisan consensus has moved toward agreeing that the invasion was a mistake. While acting as undersecretary of state for arms control for George W. Bush, Bolton was emphatic that there was proof Iraq possessed weapons of mass destruction. He reportedly created a dynamic in the department that led to intelligence officials being afraid of defying his unverified claims.
He has also been a member of several conservative think tanks, contributed to Fox News as a talking head and wrote the foreword for a 2010 book by two well-known anti-Islam figures.
This article has been updated with Bolton’s comments on Fox News.