I. Why Gallipoli?

By early 1915, the Western Front of World War I was a bloody stalemate. Winston Churchill, First Lord of the Admiralty (the political head of the Royal Navy) was weighing up a bold and risky strategy to break the deadlock.

The idea was a second front in Turkey. Churchill didn't come up with it - that was Maurice Hankey, Secretary of the War Council. Churchill was in fact initially sceptical, preferring an even riskier plan - the invasion of Schleswig-Holstein via the Baltic Sea. But eventually he came around to the idea of an operation in the Dardanelles, and began obsessively advocating for it within the government.

Churchill had a military background. He knew more about war than the politicians, and more about politics than the military men - putting him in a unique position of strength around the tables where decisions were made. This, combined with his stubbornness and his famous mastery of the written and spoken word, allowed him to forcefully persuade his colleagues that the Gallipoli campaign would be a success.

But it was the opposite, with both the naval assault and the amphibious landing totally failing to meet their objectives. Despite the best efforts of the troops, the expeditionary force had to to make a humiliating withdrawal after eight months with nothing to show for it except a quarter of a million casualties and a lot of wasted resources.

Far from being the shortcut to ending the war, Churchill's new front ended up looking a lot like the old one: costly, bloody, and apparently pointless.

II. Immediate aftermath and medium-term impact

Churchill avoided official blame for the fiasco. The Dardanelles Commission was set up in 1916 to investigate what had gone so badly wrong, and issued two mild reports that blamed a lack of prioritisation from the government and the over-optimism of General Sir Ian Hamilton, who had commanded the expeditionary force.

Historians don’t put much stock in these reports because Hamilton tampered with witnesses to ensure that he came out looking better than he should have, and they were clearly deliberately bland so as not to undermine the ongoing war effort. In fact, this commission set the precedent in Britain that government inquiries on conflicts should not take place until the conflict is over.

Still, the political consequences were immediate and severe for Churchill. He was demoted to a meaningless cabinet post and, in November 1915, resigned from the government entirely. He effectively quit politics for a time to serve on the Western Front himself - although he remained an MP.

Churchill made it very easy for people to scapegoat him. He had entirely hitched his wagon to the Dardanelles strategy, hectoring and borderline bullying his colleagues into supporting it. Characteristically for a man of such gargantuan self-belief, he did not hedge his bets. He was utterly convinced - at least outwardly - that the idea would work.

One has to imagine that he wanted to be seen as a singular military genius who - using a bold and visionary strategy - saved thousands of lives through a swift victory in a bloody war. Instead, when it was a disaster, he had nowhere to hide.

Paul Addison states that the disaster confirmed flaws in Churchill's character that his colleagues were already very familiar with. Chiefly, that he was able to develop radical solutions to problems and persuade others of their virtues, but that he lacked the judgement to carry them out effectively.

The impact on his reputation among the general public is harder to gauge. There were no opinion polls or approval ratings in those days, and due to propaganda and wartime secrecy, the public was never given the full picture of the war.

Immediately after leaving the Admiralty, he went back to his Dundee constituency to make a thunderous speech about the war. He was defiant and unapologetic about his naval strategy, and apparently the crowd received his words enthusiastically. Though this was pre-Somme, and the public mood was not yet turning against the conflict.

Even so, the newspapers treated Churchill as a pariah. He was heavily criticised in the press throughout 1916, with one article in the Daily Mail describing him as “a megalomaniac politician” who had “risked the fate of our Army in France and sacrificed thousands of lives to no purpose” with his Gallipoli blunder.