What if Niall Ferguson had not declared war on Pankaj Mishra in 2011? As Ferguson argues in his book Virtual History: "It makes sense to compare the actual outcomes of what we did in the past with the conceivable outcomes of what we might have done."

Thus counterfactualists may want to ask how things might stand had Ferguson not chosen to respond with escalating legal threats to Mishra's unfavourable review of Civilization in the London Review of Books. Mishra had made comparisons with work by the American white supremacist writer Theodore Lothrop Stoddard, which Ferguson chose to interpret as a libellous accusation of racism: "At the very least, Mishra owes me a public apology for his highly offensive and defamatory allegation." He also expressed anger, in a style perhaps more reminiscent of Charles Pooter than Stoddard, at being described as "immune to… humour and irony" (generously, no formal apology was demanded for this additional affront). Now, Mishra's responses only having further inflamed him, Ferguson is threatening the LRB's editor with litigation, telling her, he discloses: "Don't force my hand by forcing me to put it in the hands of lawyers."

Did it have to be this way? Imagine the outcome if Ferguson had contented himself, as countless indignant academics have done in the past, with letters, bitterly addressing Mishra's wrongness as he sees it. That would have been nothing out of the ordinary for a journal which has hosted livelier engagements, or for Ferguson, who would thereby have retained his place in the celebrity firmament as the brilliant telly historian with, by his own admission, a huge talent for grudges. "Get the bastard when the opportunity arises," is a scholarly precept he shared recently with Decca Aitkenhead. "Never underestimate the irate Professor Ferguson." Although he began his first letter of protest to the LRB: "It is not my habit to reply to hostile reviews", this self-restraint is not uniform. A Guardian article by Seumas Milne was described as "a shocking piece of crass misrepresentation".

Occasionally, the never-to-be-underestimated Ferguson prefers to pursue his vendettas on ICorrect, a site where fellow celebrities such as Cherie Blair and Naomi Campbell pay $10,000 for the chance to rebut false accusations. Sir Michael Caine, for instance, has used ICorrect to record that he never said: "Not many people know that." For his part, Ferguson insists that he, in fact, won a debate with another of his intellectual opponents, the economist Paul Krugman, quoting in his own support a headline from a Korean newspaper: "A great Nobel prize winner humiliated like a dog in Korea". A subsequent entry dismisses a hostile review of Civilization by another critic, Alex von Tunzelmann. "This critique would be more impressive," says Ferguson, clearly floundering without his Korean supporters, "if von Tunzelmann had bothered to read the book."

What if Ferguson had, rather than threaten Mishra with libel, registered his objections, as in the past, in Naomi Campbell's journal of record? Most general readers, as well as most historians, would have remained unaware that he frequents this preposterous website and his judgment would not have risked, as a result, becoming a matter for contemptuous speculation (assuming, of course, the ICorrect entries do not illustrate a well-developed sense of humour and irony).

Is Ferguson's recourse to libel threats, as some believe, just another way of advertising his book? If increased sales do not ensue, the unfolding drama is sure to remind a lot of people how recently he urged US neocons to build a new empire. Indeed – although his formidable energy can make it hard to keep up – I understand he was still endorsing the export of western freedom by force at around the time Michael Gove adopted him as a history mentor, tasked with transforming flabby thematic teaching into something closer to Our Island Story. As Sir Michael Caine once said, not many people know that.

As for the impact of his actions on historians in general, it could be argued that, even without Ferguson's contribution, his profession had already been lavishly embarrassed by David Starkey on Jamie's Dream School, and by the extraordinary activities of Orlando Figes, who was last year unveiled as the author of abject attacks on his rivals, stealthily posted on Amazon.

Now, clearly, a hack is in no position to criticise a historian or not until it is revealed that a historian once did something as vile as put a letter in JK Rowling's daughter's school bag. But when Gove is extolling history's prime role in helping students "separate falsities from the truth", it cannot help this argument that Figes remains Professor of Sockpuppetry (and History) at Birkbeck, University of London.

What was unforgivable about Figes, the author of The Whisperers: Private Life in Stalin's Russia, and excruciating for his targets, fellow academics who feared being ruined, was his threat of libel action, to close down questions about his activities. After Figes was exposed (following an unsuccessful attempt to attribute the attacks to his wife), one victim, the great historian Robert Service, wrote: "The public interest in this squalid little story is that if someone is wealthy and malicious enough it is possible to tread on the throat of free and open discussion in this country almost with impunity. I was close to caving in at times simply because I lacked Figes's financial resources."

Aside from its prattish appeal and Ferguson's official role, i/c Our Island Story, the public interest in his behaviour is the same. Although habitually dismissive of the UK, this US resident can still enjoy something uniquely British and precious that is unavailable in his adopted home: libel laws that allow the wealthy and vengeful to censor public discourse. A high-profile campaign for reform has not halted a procession of libel actions, by both tourists and homegrown censors, designed to silence authors and publishers. A judge is currently considering a libel action against a contributor to the Richard Dawkins website, the Richard Dawkins Foundation, and Amazon, brought by a self-published author.

As with Figes, that chronicler of mute oppression turned would-be oppressor, Ferguson's earlier incarnation, as a champion of free expression, only aggravates the spectacle of him now trying to stifle it, for no better reason than pique. "We've got to be able to talk about this stuff," he said of David Starkey's recent musings on the race aspects of the riots when they were attacked by some Unison-minded speech police as unsayable. It would be small consolation, in the event he got anywhere with his attack on the LRB, that the only reputation to suffer would be that of Professor Niall Ferguson, who once called a column "a designated free-speech area". Nowadays, he likes to extol his wife, Ayaan Hirsi Ali's superior appreciation of western liberties. "We take freedom for granted," he has said, "and because of this we don't understand how incredibly vulnerable it is." Maybe it's beginning to dawn.