Rob Crilly is a British journalist living in New York. He was The Telegraph's Afghanistan and Pakistan correspondent and was previously the East Africa correspondent for The Times of London. The opinions in this article are those of the author.

(CNN) Are these the end times for both America and the world?

An out-of-control ego intent on promoting its own interests -- with no regard for the usual norms and conventions -- dishes the dirt with cheap shots at opponents and boorish jokes about their personal appearance.

In so doing, it diminishes the standing and the status of one of America's great institutions, risking deadly confrontation and a spiral into war.

Its new book, "A Higher Loyalty," to be published on Tuesday, has already attracted huge fanfare, shattering embargoes in a tidal wave of excitement.

Not for the first time, James Comey's Ego propels itself to the center of American politics and the world stage.

The book's pages detail how the Comey Ego first became a household name during the 2016 presidential election, taking on a pivotal role even as it sowed the seeds of its own downfall.

It was not enough, you'll remember, that the FBI had pored through Hillary Clinton's emails as it investigated her use of a private email server and concluded that there were no charges to answer: James Comey's Ego wanted to be the one to announce it.

Instead of simply dropping the matter, the result was a news conference at which James Comey's Ego spent 10 minutes denouncing Mrs. Clinton's email practices before getting to the fact that no further action would be taken. The news media got their headlines, as did James Comey's Ego.

Worse followed when the FBI received a new batch of emails to probe. Just 11 days before election day, James Comey's Ego wrote to Congress announcing that the investigation was being reopened.

JUST WATCHED Comey: Briefing Trump felt like out-of-body experience Replay More Videos ... MUST WATCH Comey: Briefing Trump felt like out-of-body experience 02:49

Not everyone in the office thought it a wise move, according to excerpts from the book.

One colleague -- perhaps not given to the same sort of confidence and psephological foresight as the then-FBI director -- according to excerpts, asked: "Should you consider that what you are about to do may help elect Donald Trump president?"

"No," came the answer of a figure so certain of a Hillary win that no opportunity for self-promotion need be missed.

At this point you might be forgiven for thinking we had rather heard enough from James Comey's Ego. Having helped elect Mr. Trump, wouldn't the graceful thing be to step back, damage done, from the public scene?

James Comey's Ego has other ideas, leaking details of presidential conversations to the media ahead of a blockbuster appearance before Congress last year.

Its once-anonymous Twitter account gave nods and winks to friends and journalists in the know -- with posts linking to FBI job ads and the sort of moody pastoral scenes designed to spark a guessing game about the author's identity.

And now we have the book, some of it based on notes kept during its time as FBI director, detailing the president's hand size ("it was smaller than mine but did not seem unusually so") and tie-length ("too long"). It picks over Trump's perhaps not unreasonable fury at unsubstantiated reports he cavorted with prostitutes in a Moscow hotel.

It all makes for unedifying stuff. Not so much the high-minded work of a whistleblower with a cause as a lurid rant of an ego untethered. Is this how former directors of the FBI are supposed to behave?

And it comes with dangers. At a time when this White House is under intense scrutiny, as investigators close in on former officials and their lies, at a time when Trump is weighing what might be the most consequential decision of his presidency and mulling whether to launch punishing military strikes against Syria , along comes James Comey's Ego, nursing a grievance.

If we know anything at all about the ego in the White House it is that personal slights provoke immediate rage and unilateral distraction of the headline-generating kind.

After first helping Mr. Trump win power, James Comey's Ego has thrown itself back into the political maelstrom and into the Syria calculus.

At least we perhaps now understand the origins of the book's title, A Higher Purpose. For did you know that when James Comey's Ego draws itself up to its full height, it stands a full six feet eight inches tall?