It has been a while since one of the president's men has been declared a hero of the republic. The pattern should be familiar by now: James Comey, a GOP hack if not a quasi-traitor for his last-minute announcement about Hillary Clinton's emails, was elevated in his own lifetime into a kind of walking Lincoln Memorial of patriotic selflessness after a show-boating hearing, a tedious memoir, and an endless series of probable leaks. The same thing has happened with every other former confidante of President Trump or official who has left the executive branch, including, rather quietly, Steve Bannon, whose indiscreet conversations made possible the 2018 anti-Trump bestseller Fire and Fury. Heck, even Omarosa was briefly feted as a member of the #Resistance.

Now it is John Bolton's turn to undergo public metamorphosis from dangerous reactionary warmonger who would happily nuke Iran to selfless, devoted public servant. Once again, it is because of a book, albeit one that has not yet been published.

According to The New York Times, a draft of Bolton's upcoming memoir confirms that Trump at least briefly insisted upon delaying the disbursement of $391 million in aid to Ukraine until the country started investigating Joe Biden and his son Hunter. The story, which contains no direct quotations from the text, also suggests that Mike Pompeo, the secretary of state, was wary of Rudy Giuliani's involvement in American diplomacy and that Bolton had raised his and Pompeo's concerns with the attorney general, William Barr, which Barr has denied. The story, at least as articulated by the Times, seems to reinforce what impeachment-hungry Democrats have been arguing for months.

But it's worth asking what Bolton's motivations are here. If what he has written is true and he thinks it is as serious a matter as the Times apparently does, was receiving a $2 million advance and imparting his secrets to Microsoft Word really the best means of bringing it to the attention of the American people? What Bolton's conduct — not least the sudden leak of the book's contents, which he cheekily blames on the White House — tells us is that he is not interested in principles. This is not about the impeachment process itself or the violation of supposed norms or even about genuine foreign policy disagreements he seems to have had with the administration: It is about personal revenge.

Do motives matter? Certainly not to Democrats, who will be as happy to trade on revelations Bolton has made out of spite as they were with past Trump defectors. The president's allies, meanwhile, will claim (not wrongly) that Bolton is simply a disgruntled former employee whose recollections can safely be ignored. In any case, nothing Bolton has written is likely to change anyone's mind about the underlying facts of the Ukraine affair. The information his book is said to contain confirms everything that the president's opponents have said all along. If it was not persuasive before it will not change the balance of opinions now, when it is repeated by someone whose animus towards the administration goes without saying. This is why — spoiler alert — this process is still going to end with Trump's acquittal.

The real question is whether it will be enough to convince a handful of Senate Republicans to insist upon calling witnesses (including Bolton) to testify during the Senate impeachment trial? I think the answer is possibly yes. But if witnesses are called, Sen. Josh Hawley of Missouri has made it clear that he intends to force his wayward Republican colleagues — and vulnerable Democrats such as Joe Manchin in West Virginia — to vote on whether those made to testify will include both Bidens and Rep. Adam Schiff, the chairman of the House intelligence committee who is serving as the Democrats' main impeachment manager.

It is not obvious to me that forcing Schiff to provide an account of how and when he became aware of the so-called whistleblower complaint or to explain his history of support for Ukrainian nationalism would benefit his party. It is even harder to see why any Democrat would want either of the Bidens to answer questions from Republican senators and members of Trump's legal team. An incomprehensible jumble of names and dates and third-hand allegations does not make for good television, as we discovered during the House impeachment hearings: Hunter explaining why he thought he was qualified to serve as a well-paid expert on Eurasian mining infrastructure and why Joe suddenly cares so much about military aid that the Obama administration had refused to provide in the first place would be. Meanwhile, calling witnesses would likely keep Elizabeth Warren, Bernie Sanders, and possibly even Biden himself away from the campaign trail ahead of the Iowa caucus and the New Hampshire primary.

What Bolton's testimony would reveal apart from what has already been reported is uncertain. But it is impossible not to imagine that he would make for a much more compelling witness than anyone the Democrats managed to secure during the House phase of impeachment proceedings. This would be true less because of the content than due to the manner in which it would be presented. Here is someone who can speak directly to Trump's frame of mind and motivations, an old Fox News hand who knows how to tell a story. Bolton on the witness stand would be direct, forceful, and no doubt at least occasionally amusing.

For both sides in the impeachment debate the calling of witnesses would come at a considerable price. Only Bolton has nothing to lose here.