Isil are also cunning and well organised, and very hard to defeat. In less than a year, they have turned much of Iraq into a shambles. They have caused about 7.6 million people to flee their homes – anyone of a different religion, anyone who refuses to bow, anyone who won’t pay the tithes, anyone who objects to their programme of slaughter and rape. I talk to a Shi’ite muezzin from a Mosul mosque, and as we sit on the floor of his tiny bivouac, he alternately weeps and rants as he describes the failings of the Iraqi army. They have done nothing to protect him. Iraq as a country is no good, he says – and as far as he is concerned, Mosul should be handed over to the Kurds.

The UK is pledged to help these Peshmerga, and we can certainly be proud of what is being accomplished. The RAF has launched dozens of sorties, dropping Paveway and Hellfire munitions on the Isil insurgents, often with success. I went up in the hills, about 30 miles from the front, to watch men and women from the British Army giving tuition in the basics of warfare. There on rolling green terrain – looking a bit like a shooting party in northern Spain – the weather-beaten Peshmerga were learning to advance in formation, to avoid ambush, to take out wounded comrades. There is no doubt that the Kurds are grateful for what we are doing, and especially for help with their 1.5 million refugees.

But it is important not to exaggerate our military contribution. We have given them 40 heavy machineguns and half a million rounds, and we have a total of 75 troops deployed, with very strict rules of engagement. We are not even teaching them such essentials as how to remove an improvised explosive device. I look at these Kurds and the scale of the challenge they face – Mosul is still occupied by Isil – and I cannot help wondering if we could do more. Those anti-tank weapons that worked so well the other night: they came from Germany. Couldn’t we send some more?

Of course I understand the anxieties of the UK Government: the strong and justifiable aversion to sending British ground troops to the frontline. Then there is the basic uncertainty about how any more weapons might ultimately be used, and against whom. It may be that the future for Iraq is a more federal structure, with even more autonomy for Kurdistan – but no one wants to see a violent break-up; no one wants a disintegration of relations between Baghdad and Erbil, the Kurdish capital.

All these political questions are important and delicate, but they strike me as fundamentally questions for another day. The immediate task is to help the Kurds defeat the forces of darkness and hate. It is hard to think of another conflict where righteousness coincides so overwhelmingly with the British interest. In a miserable region, Kurdistan is an oasis of democracy, tolerance, prosperity, openness and relative gender equality. Since John Major’s 1991 no-fly zones, the Kurds have been vehemently pro-West, and particularly pro-British. With the sixth-biggest notional oil reserves in the world, Kurdistan is a huge opportunity – and already has the most successful Jaguar Land Rover showroom in the Middle East.

Now is exactly the time, when things are tough, for us to step up our support: encouraging more trade, and more direct flights from London to Erbil, and above all to spread the news to British business that Kurdistan is really different, and in some ways better. And we should consider intensifying our military support. In a struggle against savagery that washes up on our shores, their cause is our cause.

When the airplane was in its infancy – barely 10 years after Wilbur and Orville Wright had taken off from Kitty Hawk – he was repeatedly going aloft in these hair-raising contraptions. And when his instructors were killed, and when his family and friends were begging him to desist, he continued to fly. He got lost in a storm over France in 1919, and almost perished. He had a serious crash in Buc aerodrome in France, when the plane’s skis hit the edge of a concealed road at the end of the runway, and the machine did a somersault – like a shot rabbit, he said – and he found himself hanging upside down in his harness. The following month he had an even worse crash at Croydon – smashing into the ground so hard that the propeller was buried, his co-pilot knocked out.

You read these accounts of disaster and you wonder what was going on in his head, that made him continue with something so obviously risky. Why did he push it? Why, when he served in the trenches in the First War, did he go out into No Man’s Land not once but 36 times, going so close as to be able to hear the Germans talking? Yes, he wanted to be thought brave, and yes, to some extent he was a self-invented person. But in the end the man he created was the real Churchill.

He dared to say things that no one would dare say today, and to behave in ways that would terrify the milquetoast politicians of the 21st century. When Bessie Braddock, the Socialist MP, told him he was drunk, he really did retort that she was ugly, but he would be sober in the morning. On being told that the Lord Privy Seal was waiting to see him, it seems that he really did growl out – from his position on the lavatory – that he was sealed in the privy and could only deal with one shit at a time. During one of his many infuriating conversations with Gen de Gaulle, in the depths of the war, he really does appear to have used his superb and menacing franglais: “Et marquez mes mots, mon ami, si vous me double-crosserez, je vous liquiderai.”

He imposed his own exuberant and uninhibited style on events. Who else could have wandered naked round the White House, or appeared before the US press corps wearing a bizarre purple romper suit of his own design, tailored by Turnbull and Asser? He truly did begin the day with champagne, or a glass of whisky and water, and then go on all day to consume quantities of booze that would have felled a bullock. He could have a three course dinner accompanied by champagne, white wine, red wine and brandy – and then go into his office at 10 pm, and start dictating vast periods of prose, much of it brilliant and original.

He didn’t just pose with cigars, or wave them around for Freudian effect. He smoked with a gusto that would today be unforgiveable – perhaps 250,000 in his lifetime, mainly Romeo y Julietas. The stubs were collected and given to the gardener at Chartwell (the poor chap died of cancer).

He seemed to be running, in other words, on a type of high-octane hydrocarbon that was available to no one else; and it was this energy, combined with his boldness, that produced his astonishing political fertility.

Our children are taught roughly what he did in the Second World War – but we have been in danger of forgetting his crucial role in helping to win the First. It is no exaggeration to say that he was one of the fathers of the tank – whose battlefield breakthroughs were eventually of critical importance; and it was his sedulous preparation of the Fleet, as First Lord of the Admiralty – not least the historic geo-strategic decision to convert the dreadnoughts from coal to oil – that meant England never lost control of the Channel.

His legacy is everywhere in the modern world. He helped to found the modern welfare state, pioneering unemployment insurance and other social protections in the years before the First World War. He was instrumental in the creation of modern Ireland, of Israel, of the map of much of the Middle East. He was one of the very first, in the Thirties, to adumbrate the idea of a “United States of Europe” – though he was ultimately ambiguous about exactly what role Britain should play.

It is Churchill’s shaping mind that still dominates our thinking about the world role of Britain – at the centre of three interconnecting circles: the Atlantic alliance, the relationship with Europe, and the relationship with the former Empire and Commonwealth.

Yes, of course he made catastrophic mistakes. He cannot be entirely exculpated for Gallipoli; he misread the public mood over the Abdication; it is hard to read some of his remarks about Indian independence without a shudder of embarrassment. But in these very disasters we see his boldness and determination to stick with the course he had embarked on, even if everyone was saying he was wrong.

And it was precisely that stubbornness and that bravery which was required in 1940. Think yourself into that smoke-filled room in May, that fateful meeting of the seven-strong War Cabinet. France had fallen; Europe had been engulfed by the Nazis; the Russians had done a nauseating deal with Hitler; the Americans were standing on the sidelines. Britain was alone, and the pressure to do a deal was overwhelming. The City wanted it; much of the media wanted it; Halifax wanted it; Chamberlain wanted it; Labour would have gone along.

It was Churchill and Churchill alone who was decisive in ensuring that Britain continued to fight. It was Churchill who was crucial to bringing America in – more than two years later. If Churchill had not been Prime Minister in 1940, there seems little doubt that Britain would have made an accommodation with evil – letting Hitler have his way and plunging Europe into darkness and barbarism. No one else round that table had the guts to do what he did; and it is to him, therefore, that the world owes thanks for the eventual victory over Nazism, and the 70 years of peace that have followed.

The more you study Churchill, the more I hope you will share my conviction that there has been no one remotely like him before or since.

It comes as a host of events and funding programmes were announced to mark the 50th anniversary of Churchill’s state funeral, which falls on January 30.

A trio of commemorative events will be held on the day including a special service in the Houses of Parliament, the laying of a wreath in Westminster Abbey and a flotilla along the Thames led by the vessel which carried Churchill’s coffin in 1965.

Speaking after the launch event, Ms Soames, brother of Tory MP Sir Nicholas Soames, was asked whether Mr Johnson shared any characteristics with Churchill.

“Yes. Journalistically, certainly, and wit,” she replied, adding that in the future more leadership similarities may appear.

Asked about Paxman’s suggestion Churchill would be unelectable today, she said: “Well, I just don’t think that’s true. I think that Churchill’s virtues were so great and, in the same way that Boris is very popular, I think Churchill would be very popular because he’s got this amazing gift of the gab and he had a genuine commitment to ordinary people.”

Asked if Paxman was wrong, she added: “Yes. Paxman’s got a programme to promote. … It’s certainly true that Churchill was an egotist and I think Jeremy Paxman may easily be one too.”

Ms Soames also praised the London Mayor’s “absolutely terrific” book on Churchill, saying he had raised his game and produced a “very accessible … warts and all” account.

News that Churchill’s grandchild believes Mr Johnson shares characteristics to the man named the Greatest Briton of all time in a 2002 poll is a timely boost for the London Mayor.

Mr Johnson played down comparisons with the Tory wartime prime minister in the past but was seen by some as courting such suggestions with his recent book, The Churchill Factor: How One Man Made History.

Writing in the Radio Times to mark the 50th anniversary of Churchill’s death, Paxman described him as “a ruthless egotist, a chancer and a charlatan at times”. “Would he be electable now?” Paxman asked. “I fear not. He was a man of his time, a parliamentary one-off who’d be suffocated by the spinning and posturing that pass for politics today.

“Being both good and bad, adequate and inadequate, selfish and public-spirited, is just being human. Maybe — though he or she never seems to have been especially visible — there was someone else who might have led the country in its darkest times.”

No wonder that so many naturally bossy and Left-wing people are thinking of going for the Greens, rather than Labour. At least they have a world-view; at least they know what they think. For the last few years I have had the joy of engaging with the Greens in London, and I believe I understand their mindset pretty well. They don’t like capitalism, they don’t much like economic growth and they hate, hate, hate anything to do with the motor car. They especially hate and fear the advent of low-carbon vehicles, because they consider these to be an unfortunate diversion from their main purpose: to drive everyone out of private cars – with their horrid connotations of individual liberty and autonomy – and on to public transport.

On some points I agree with the Greens; on some I disagree strongly. But when I think of my friend Jenny Jones, now Baroness Jones, I see a doughty and often successful campaigner for a set of environmental or pseudo-environmental objectives. She was at all the mayoral debates in the run-up to the London election in 2012 and enlivened them. David Cameron is absolutely right in taking his stand on her behalf. Of course the Greens should be in the TV showdowns. They may be occasionally batty, but at least their case is gaining ground with the public, and at least it has some bravery and rigour about it. That is not the case with the hopeless hodge‑podge of Milibandery.

Just in the period since Christmas, the Labour Party seems to have executed no fewer than 21 U-turns – many of them junking their previous green policies. They were going to bring back a pro-bike quango called Cycling England; now they are not. They were going to ban food waste going to landfill; now they have given up. If the Greens are watermelons – Lefties disguised as environmentalists – then Miliband is a ripening tomato, moving conspicuously from green to red.

In fact, I am not sure how green Ed ever really was. His backers in the media claim that he was responsible for some kind of midnight breakthrough communiqué at the Copenhagen climate change conference in 2009.

Well, I was at Copenhagen, and I don’t remember any breakthrough at all – the whole thing was a fiasco – and I certainly don’t remember any intervention by Ed. And the reason I was there was because we in London were trying to promote a serious and sensible agenda for installing insulation, retrofitting homes, and so cutting fuel bills.

When we went to see the secretary of state at the Department of Energy and Climate Change (E Miliband) I was amazed by how little he seemed either to know or to care. He was much more interested in gossip than in a long-term programme for the country – and I fear the same is true today.

Yesterday’s paper contained a wonderful account of how he nearly died in a fire in Doncaster, during a long stay with the former mayor of that town. He took it into his head to move a convection heater off a pair of bricks and plonk it on the carpet. Both the carpet and the under-carpet ignited, and gave off such noxious vapours that Ed was sitting zonked in an armchair, in danger of being asphyxiated – until he was saved by his quick-thinking neighbour, who tipped him into the garden.

Miliband later made amends by buying a carpet to cover the burns, though the effect was slightly spoiled when his hosts realised that it was a Muslim prayer mat.

What’s that burning smell? It’s another giant hole appearing in Ed Miliband’s policies – and there isn’t a mat big enough to cover them.