One of the recurring scenes of the Trump era has been the president holding forth in some splenetic rant from the cabinet table flanked by his top officials gazing into the middle distance with frozen smiles or else looking resolutely downwards as if they had made a startling new discovery about their thumbs.

It is a tableau that always invites speculation on what can be going through the minds of these pained accomplices and now we have at least a partial answer. One among them has brought out a book giving voice to those thoughts, but we do not know who.

The book is by Anonymous, described on the cover as “a senior Trump administration official”, the same one who wrote an unsigned essay in the New York Times in September last year, declaring they were “part of the resistance Inside the Trump administration” seeking to thwart the craziest impulses. Anonymous is now a year older, wiser and more depressed.

“My original thesis in the New York Times was dead wrong. Americans should not expect that his advisers can fix the situation. We cannot. The question is what to do next,” Anonymous writes in A Warning, a book- length exposition of life in the bizarre court of King Donald. The bottom line is that things look as appalling and chaotic from inside the administration as they do from the outside.

Anonymous describes a “bizarre sense of fraternity” among senior officials “like bank robbery hostages, lying on the floor at gunpoint, unable to sound the alarm, but aware that everyone else was stricken with the same fear of the unknown”.

The author sees himself or herself as part of the “steady state” (as opposed the “deep state” of the darker imaginings of Trump loyalists), who joined the administration early on, out of a mix of duty and optimism that the unlikely president would grow into the role. Then – when that began to look absurdly unlikely – the steady staters stayed on to try to contain and mitigate Trump’s whims until they realised they had become “glorified government babysitters”.

Presenting a fully fledged policy document ‘would be like speaking Aramaic to Trump through a pillow’

These officials quietly compare notes and pool their shared shock and despair. According to Anonymous, there was half a plan to stage a mass resignation at one point as a way of raising the alarm about the seriousness of the situation, but the scheme was abandoned as being too destabilising to the country.

Instead, these officials have continued to seep out of the administration in a steady stream of resignations and dismissals. It is not entirely clear whether Anonymous is still on the inside, constantly in fear of discovery. But if I had an anonymous source burrowed deep inside the administration, I would want a lot more colour and anecdote than we are given in A Warning. We do learn that Trump has the insane idea of designating migrants as “enemy combatants” and sending them to Guantánamo Bay. We also get a little more detail on the relentless dumbing down of presidential briefings. Policy papers were condensed to PowerPoint presentations with a handful of slides, which became three main points, and then finally the advice to newcomers was “come in with one main point and repeat it over and over again”, couching it in terms of “winners and losers”, preferably with a really strong graphic.

Anonymous recalls the reaction to a hapless aide who ignored the advice and presented pages of briefing notes. “What the fuck is this?” Trump shouts. “These are just words, a bunch of words. It doesn’t mean anything.” Presenting a fully fledged policy document, the author observes memorably “would be like speaking Aramaic to Trump through a pillow”. “Even if he tried very hard to pay attention, which he didn’t, he wouldn’t be able to understand what the hell he was hearing,” Anonymous writes. Various unnamed officials are frequently cited saying such things as: “This place is so fucked up ... There is literally no one in charge here” – which frankly has become the archetypal unattributed quote from the Trump era, familiar from a thousand newspaper stories.

Anonymous acknowledges that there is something strange about Trump’s obsequious relationship with Vladimir Putin but has no definitive ideas about what lies beneath it, other than a general admiration for dictators who run their countries as he would like to run the US.

The author predicts that there will be a lot more compelling stories to emerge from the administration at a later date, to which any reader would be entitled to ask why they were not informed of that before they bought this book. By way of explanation for its surprising blandness, the author explains early on that too many details could compromise national security or help blow the writer’s cover.

‘Anonymous acknowledges that there is something strange about Trump’s obsequious relationship with Vladimir Putin.’ Photograph: Brendan Smialowski/AFP/Getty Images

Speculating about the author’s true identity has become something of a niche sport in Washington. The sleuths should perhaps be looking for someone with a classical education. The text is littered with the sayings of Plato, Aristotle and Marcus Aurelius. An extensive middle section is devoted to measuring Trump against Cicero’s virtues of leadership – an odd, rather pointless exercise, a bit like judging Boris Johnson by the attributes required to be a world class ballerina. There is little surprise that the president scores badly in every department.

The classical stuff is laid on so thick it could be a misdirect, designed to cast suspicion elsewhere. Leak investigators might instead look for an admirer of the late senator John McCain. The author of A Warning was provoked into writing the first cry for help in the New York Times not because of Trump’s obvious misogyny or racism, or attachment to Putin, but because of the president’s peevishness on McCain’s death in August 2018, sulkily ordering flags raised after the first day of mourning and failing to put out a proclamation. The warning in the book’s title refers to the implications of a second Trump term. The president is already ignoring the law, and the supposedly co-equal authority of Congress, putting loyalists in top position in an acting capacity, so they need not be confirmed by the Senate. Anonymous predicts the republic is likely to unravel at an accelerated rate if Trump wins re-election.

On the world stage, the author observes that the US has been extraordinarily lucky so far not to have undergone a monumental international crisis since Trump took office. “We have not suffered a major attack against the United States or been forced to go to war, but it’s only a matter of time before that luck runs out,” Anonymous predicts, asking the reader whether they really want to risk keeping the US nuclear arsenal under Trump’s unchallenged stewardship for another four years.

Providing more detail of the moment members of the administration contemplated invoking the 25th amendment, relieving the president of power if a majority of the cabinet and the vice president deem him unable to discharge his duties, Anonymous contends if enough cabinet members had signed such a document, Mike Pence would have put his name on it.

“Armoured vehicles would race across town to the US capitol building and a protected courier would walk the document into the hands of congressional leaders,” the book suggests. However, the author and the would-be co-conspirators quickly had second thoughts, reasoning that Trump would resist and denounce the move as coup, possibly triggering conflict across the country. “Violence would be almost inevitable,” Anonymous concludes.

The book is current enough to consider the impeachment proceedings now under way, urging Republicans to follow the law rather than partisan loyalty, before rejecting that option too as an unsatisfactory means of toppling an elected president. Ultimately, Anonymous deems the 2020 election to be the country’s best chance of waking up from its Trumpian nightmare. The author encourages fellow Republicans to look beyond tribalism, and Democrats to put up a centrist candidate that can unite an anti-Trump majority, or muses about a third-party candidate emerging from the heartland.

A Warning ends then with a rousing call to the ballot box, but it fails to answer the question that hangs over almost every page: why heed the counsel, however urgent, of someone who is not prepared to reveal who they are?

• A Warning is published by Little, Brown (£20). To order a copy go to guardianbookshop.com or call 020-3176 3837. Free UK p&p over £15, online orders only. Phone orders min p&p of £1.99.