The moral of the story is that those who make a living from the expression of controversial opinions (and for that matter Bloggers and the like who do it as a hobby) really shouldn't run to the libel laws when they find themselves criticised (however unfair the criticisms might seem).
Last year when Professor Orlando Figes got himself in a spot of bother over anonymous reviews he posted on Amazon, the problem was less that he posted the reviews at all, but rather his threat to sue when (correctly) accused.
Ferguson is always likely to arouse the ire of those who disagree with his neo-Thatcherite take on history and a hostile review in a small-circulation publication is hardly likely to damage his reputation. Figes' trashing of fellow historians' books would have been little more than an amusing curiosity if he hadn't tried to silence them when they rumbled him.
It might be a different matter if, like poor Christopher Jefferies, they were wrongly accused of a vile crime. But for the most part anyone who courts contoversy has to be able to take it as well as give it. The best way to deal with unfair criticism is to rebut it in print. Those tempted to sue would be better taking a couple of aspirin and having a lie down until the mood passes.
Green's article is worth reading in full, but I was rather taken with one quote in it. When A.J.P. Taylor's The origins of the second world war was savaged by Hugh Trevor-Roper, who said it would harm his reputation as a serious historian, Taylor replied:
The Regius professor's methods of quotation might also do serious harm to his reputation as a serious historian, if he had one.As far as I am aware, Trevor-Roper didn't sue.