WASHINGTON, Sept 11, (AP): John Bolton was in Mongolia. More than 1,200 miles (1,930 kms) away, President Donald Trump orchestrated an image for the world’s front pages by becoming the first US president to set foot in North Korea, shaking hands with Kim Jong Un on the north side of the demilitarized zone.

The distance was telling. Bolton, a longtime critic of diplomacy with North Korea, had scheduled his foray to Mongolia weeks before Trump’s impromptu invitation to meet Kim. But the national security adviser’s isolation at such a high-profile moment underscored the growing disconnect between the two men.

Their repeated clashes on policy and style reached an exclamation point Tuesday when Trump ousted Bolton with a tweet. This account of how their relationship unraveled is based on interviews with current and former administration officials and Republicans close to the White House. They spoke on the condition of anonymity to discuss private deliberations.

It was a marriage that was never going to last: Trump and Bolton rarely saw eye to eye on global hotspots. The national security adviser held far more hawkish views than the “America first” president on matters like Iran, North Korea and Afghanistan. “John Bolton is absolutely a hawk,” Trump told NBC in June. “If it was up to him, he’d take on the whole world at one time, OK? But that doesn’t matter because I want both sides.”

Trump does value disagreement and jockeying among his staff. But he came to believe that Bolton’s presence spooked foreign leaders. And he eventually grew weary of the national security adviser’s bureaucratic knife-fighting. By the spring, Bolton found himself cut out of important White House meetings and the president’s perceived diplomatic triumphs, including the historic visit to North Korea.

As Trump met with Kim, Bolton was photographed shaking hands with Mongolia’s secretary of state — an image that decidedly did not lead cable news. While Trump’s visit to Kim was a spectacle largely of his own making, Bolton’s more modest outreach to Mongolia was similarly his own grand design, meant to check Russian and Chinese influence in central Asia. The two trips encapsulated their opposing world views.

In the hours before Bolton left Trump in Seoul to head for Ulaanbaatar, Bolton was in a meeting with the president in which Trump paid tribute to the officials with him — or at least tried to. “And Secretary of State Pompeo is here,” Trump said. “Mike Bolton — John Bolton — is here.” Reporters spotted Bolton glowering at the slight. It would not be the last.

Trump never liked Bolton’s mustache. The president has spent a career fixed on image, prizing striking looks and frequently boasting about family members and Cabinet officials who look like they “stepped out of central casting.” Bolton’s bushy mustache simply didn’t fit the part. Bolton, a former ambassador to the United Nations and then a fixture on Fox News as a national security commentator, nearly entered the 2016 presidential campaign himself to push his hard-nosed foreign policy. His neoconservative credentials never meshed with the isolationist vibe of Trump’s campaign but, during the presidential transition, there was Bolton striding through the gilded lobby of Trump Tower to meet with the president-elect.