Bolton has been a leading voice for regime change and U.S. interventionist policies in Venezuela, Iran, Cuba and other countries around the world over policies that do not fit within U.S. interests.
"I informed John Bolton last night that his services are no longer needed at the White House. I disagreed strongly with many of his suggestions, as did others in the Administration, and therefore....," Trump said in a tweet Tuesday morning.
Bolton, who took up the post in April 2018, replacing H.R. McMaster, had sometimes been at odds with Secretary of State Mike Pompeo, one of Trump's main loyalists.
Offering a different version of events than Trump, Bolton tweeted, "I offered to resign last night and President Trump said, "Let's talk about it tomorrow."
Trump had sometimes joked about Bolton's image as a warmonger, reportedly saying in one Oval Office meeting that "John has never seen a war he doesn't like."
In January, during a televised address, the words “5,000 soldiers in Colombia," were seen scrawled across a notebook "carelessly" carried by Bolton. Within a few days, several planes, including one C17A cargo plane Globemaster - used for military transport - and one Boeing 737, landed on the outskirts of Bogota at Air Command Military Transport (Catam) airport.
Bolton, a conservative, is a strong proponent of unilateral U.S. foreign policy and a notorious war hawk who has shown himself to be remarkably boorish and tactless for a diplomat.
Bolton worked under Ronald Reagan and was the former United Nations ambassador under George W. Bush, though he expressed contempt for the organization, as he famously said, “there is no U.N. There is an international community that occasionally can be led by the only real power left in the world, and that’s the United States, when it suits our interests.”
Bolton has advocated for the U.S. to pull out of the Iranian Nuclear Deal, which the country did shortly after Bolton was appointed earlier this year. He has also referred to Palestine as a “so-called state,” saying that it does not meet the requirements for a legitimate nation.
His view of democratically elected, progressive governments in Latin America -- specifically Cuba, Nicaragua, and Venezuela, which he’s referred to as a "troika of tyranny" -- is very much in line with his unilateral, U.S. supremacy worldview.
However, Bolton has praised Brazil’s far-right president-elect Jair Bolsonaro, who has also been an outspoken supporter of the Chilean dictatorship of Pinochet, saying his election was a "positive sign" for the region.