Bolton was not White House chief of staff John Kelly’s candidate for the job. Kelly had nothing to do with his appointment, according to a source close to Bolton. Nor was he Defense Secretary James Mattis’ choice…

It’s not just that Bolton is more hawkish on Iran and North Korea — though of course he is. It’s that Bolton knows his way around the bureaucracy and won’t take anybody’s crap. He won’t show deference to Mattis or the generals, say sources who know him well…

Sources who know Bolton expect he will stare down Mattis, tell him when he’s wrong, and will be a Henry Kissinger-type presence in the room. Now that Tillerson is gone, he could fundamentally tip the balance of power on Trump’s national security team, senior officials expect.