Now that Mr John Bolton has finally ascended from the limbo of the green room to the Valhalla of the White House, we need to settle the first question of his tenure: Is he a "neocon" or a "paleocon"?

I have seen both terms used, the former more promiscuously, to describe President Donald Trump's new national security adviser. But they're both misdescriptions, and explaining why is a useful way of putting Mr Trump's foreign policy team (and its distinctive dangers) in intellectual and historical perspective.