Certainly, Mrs Thatcher was the first world leader to voice alarm over global warming, back in 1988, With her scientific background, she had fallen under the spell of Sir Crispin Tickell, then our man at the UN. In the 1970s, he had written a book warning that the world was cooling, but he had since become an ardent convert to the belief that it was warming, Under his influence, as she recorded in her memoirs, she made a series of speeches, in Britain and to world bodies, calling for urgent international action, and citing evidence given to the US Senate by the arch-alarmist Jim Hansen, head of Nasa’s Goddard Institute for Space Studies…

It is not widely appreciated, however, that there was a dramatic twist to her story. In 2003, towards the end of her last book, Statecraft, in a passage headed “Hot Air and Global Warming”, she issued what amounts to an almost complete recantation of her earlier views.

She voiced precisely the fundamental doubts about the warming scare that have since become familiar to us. Pouring scorn on the “doomsters”, she questioned the main scientific assumptions used to drive the scare, from the conviction that the chief force shaping world climate is CO2, rather than natural factors such as solar activity, to exaggerated claims about rising sea levels. She mocked Al Gore and the futility of “costly and economically damaging” schemes to reduce CO2 emissions. She cited the 2.5C rise in temperatures during the Medieval Warm Period as having had almost entirely beneficial effects. She pointed out that the dangers of a world getting colder are far worse than those of a CO2-enriched world growing warmer. She recognised how distortions of the science had been used to mask an anti-capitalist, Left-wing political agenda which posed a serious threat to the progress and prosperity of mankind.