Lloyd George: war leader by John Grigg

Armed conflict can make - and break - the reputation of prime ministers, argues John Campbell

War is the ultimate test of prime ministers. Asquith and Chamberlain were broken by it. Margaret Thatcher was made by the Falklands, and if she could have hung on for another few weeks the Gulf might have saved her again; instead, it was the making (for a time) of John Major.

What it will do for Tony Blair remains to be seen (although Kosovo did him no harm). Above all, of course, the leaders who successfully prosecuted the two world wars were raised to twin pedestals as the unchallenged "greatest" prime ministers of the 20th century. (Not forgetting Attlee, who was made by the Second World War in a rather different sense.)

Lloyd George and Churchill used to be regarded as equals, with some historians rating Lloyd George the greater man. But recently the Welsh Wizard's star has faded, leaving Winston – as Mrs Thatcher always called him – as top of the prime ministerial pops.

The first three volumes of John Grigg's superb biography, published between 1973 and 1985, helped to rescue Lloyd George's reputation from the smears of Asquithian demonology, which had portrayed him merely as an unscrupulous and unprincipled intriguer. Grigg – himself a transparently good man – treated Lloyd George as a political artist whose moral failings have to be taken as the price of genius. Sexual adventures, dodgy financial dealings and a certain economy with the truth, though honestly examined, were invariably forgiven in the context of his unparalleled political creativity.

Sadly, Grigg allowed himself to be distracted by other projects, and suffered failing health. It has taken another 17 years for this fourth volume to appear, posthumously and not, in fact, quite finished. The fifth, on the post-war premiership, not to mention the last 23 years of George's life, will remain unwritten. But we must be thankful that at least Grigg reached the climax of his epic.

From his very first sentence, suggesting that the situation facing Lloyd George in 1916 was even more critical than that which Churchill inherited in 1940, Grigg sets out to judge Lloyd George's record in the First World War against the now better-remembered achievement of Churchill in the Second. Comparisons between the two wars recur throughout the book.

The problem with this perspective is that we no longer regard them as equally good causes. No one doubts that Hitler had to be defeated at any cost. But despite the invasion of Belgium and north-eastern France and the ruthless U-boat campaign that had nearly starved Britain into submission by the beginning of 1917, few now believe that Prussian militarism posed a comparable threat, or that the cost in lives lost and blighted to defeat it was not grossly – even criminally – disproportionate.

The abiding image of 1914-18 is the futile slaughter of the Western Front. To have been the prime minister who presided over Passchendaele does not seem an achievement to be celebrated, even if the Allies did win in the end.

In fact, Lloyd George was as appalled as anyone by the slaughter and did his best to mitigate it. But his position was desperately weak. He transformed the premiership out of all recognition from Asquith's gentlemanly amateurism, and in many ways did exercise an unprecedented grip on the direction of the war. Yet as the Liberal leader of a Tory-dominated coalition, he was dependent on the Conservatives for his political survival; and as a civilian head of government he could not – short of sacking them – override the strategic judgement of the generals, who in any case told the despised politicians as little as possible of their intentions. So Lloyd George's war leadership is not so much a study in power, like Churchill's, as in impotence and damage limitation.

He did achieve an immense amount. His speeches, without the benefit of broadcasting, were as inspiring and as influential in keeping public morale behind the war, despite the horrific casualties, as Churchill's in 1940-45. The dynamism he brought to the business of government was a marvel to all who witnessed it. His appointment of equally energetic "men of push and go", mainly from outside politics, as directors of manpower, shipping, food distribution, agriculture and other vital areas of the war effort was unconventional but, usually, fully vindicated.

He played a crucial role in forcing the Admiralty to accept the principle of convoys; and he finally won a protracted battle to get the generals to accept the principle of Allied unity of command, which greatly contributed to the eventual victory in 1918.

He eventually managed to remove the pig-headed "Wully" Robertson as Chief of General Staff. But he was stuck with Sir Douglas Haig as Commander-in-Chief of the British army in France until the end, and therefore with Haig's unshakeable belief that the German army would crumble at the next attack, and the dogma that the only place to win the war was on the Western Front.

Lloyd George would have preferred to sit on the defensive and wait for the Americans to arrive, while seeking to knock out Germany's weaker allies on other fronts. At the same time, he had to cope with air raids, food shortages, labour troubles and Ireland on the home front.

With all this it is perhaps inevitable that in this volume, compared with its predecessors, the irrepressible fun and humour of Lloyd George gets a bit lost under the weight of events and strategic arguments. Nevertheless, it is a grand conclusion to a great biography.

The second volume of John Campbell's biography of Margaret Thatcher will be published next year