Patrick Diamond and Giles Radice begin their thought-provoking book with the biblical adage that ‘if a house be divided against itself, that house cannot stand’. They assert that this ‘provides essential counsel for any political party that aspires to win elections and govern in a liberal democracy’.

This axiom, of course, holds true for all political parties. However, there is no doubt that ever since 1929, when for the first time in its history the Labour Party won the largest number of seats in Parliament, it has struggled to avoid division. The authors of Labour’s Civil Wars describe the ways in which this problem has dogged Labour’s efforts to become the ‘natural party of government’, a sobriquet which the Conservatives have acquired over decades, despite their far less compelling record of achievement.

The Labour Party has been beset by deep conflict and division at each of the moments when it might have been able to achieve and then consolidate long-lasting government along the lines of the Swedish Social Democrats, who were in office continuously from 1932 to 1976. Labour failed to build upon initial success, and internal discord led the party to cede power to the Tories in 1951, 1979 and 2010. In the resulting periods of opposition, new rifts came to compound that failure, which in turn made victory in the future far more difficult.

In the opening chapter, ‘Why Labour is Given to Civil Wars’, the authors identify four distinct but closely linked sources of conflict (which they credit to the historian Peter Clarke): the coexistence of competing power blocs within the party, including trade unions, the Parliamentary Labour Party and constituency grass-roots activists; ideological conflict around the fundamental direction of the party, including sharply differing views of capitalism, the functions of the state and Britain’s global role; deep strategic uncertainty about how the party should respond to and deal with social and economic changes; and personality-oriented divisions at the top of the party, which percolate down to the grassroots.

The subsequent chapters focus on five specific historical divisions: the 1931 split within Ramsay MacDonald’s Labour government; the dispute in the 1950s and 1960s between followers of Hugh Gaitskell and Aneurin Bevan; the Bennite revolt during the 1980s; the Blair–Brown tensions running from around 2000 to 2010; and the conflict arising from the election of Jeremy Corbyn as party leader in 2015.

In the first three of these cases, the causes of division were primarily economic, arising from the policies pursued by Labour governments themselves. In 1931, the main issue was MacDonald’s response to the Great Depression, which involved cutting government spending and public-sector wages, policies opposed vehemently by the trade unions and many within the party. In the early 1950s, with Britain increasing military expenditure in the context of the Korean War, divisions erupted once again over the implementation of austerity measures at home. Particularly incendiary was the introduction by Gaitskell, Clement Attlee’s chancellor, of prescription charges, which prompted the resignations of Bevan and Harold Wilson as ministers. The divisions of the 1980s can be traced back to the International Monetary Fund bailout of 1976 and the budget cuts Jim Callaghan’s government was forced to make as a result. In each case, the economic problems were followed by Labour going into opposition, where divisions were exacerbated, becoming utterly debilitating.

The enervating Blair–Brown tensions, described in the fifth chapter, are a different kettle of fish. Divisions in the Labour government of 1997 to 2010 did not result from economic failure; indeed Labour’s response to the 2008 financial crisis was effective in difficult circumstances. There were important arguments about the Iraq War, but overall the divisions were personal, fuelled by one man’s ambitions, albeit with some ideological trimmings. After Labour’s 2010 defeat, the divisions widened, symbolised by Ed Miliband’s speech following his election as leader, in which he tried to distance himself from Blair. Corbyn’s period of leadership just made things worse.

Diamond and Radice show how the experience of government can be thoroughly chastening. Almost inevitably, it leads to disappointment, as a series of overoptimistic promises are not fulfilled. The challenge for a party seeking political power in the long term, something Labour should aspire to, is how to deal with these frustrations and challenges in a way which is not morale sapping and destructive. One important element is the understanding that simple condemnation of, or disagreement with, the government of the day is not enough. An effective opposition needs to offer a plausible alternative to the government’s approach and so to be able credibly to answer the question ‘What would you do?’

In their final chapter Diamond and Radice conclude that ‘the goal of unity cannot override the imperative of a viable strategy for winning power’ and that ‘presenting a united front to voters is insufficient in the absence of a compelling programme and governing agenda’. In short, political unity is a necessary but not a sufficient condition for long-term electoral success. This conclusion is right and also important, since so many people continue to argue that discussion should be avoided because of the dangers of creating a ‘divided party’. The problem with this siren call for ‘unity’ is that it inhibits the very discussion which is essential to identify the best approach for future success.

The Conservative Party’s attitude to the need for regeneration and renewal is instructive. After 1945, the Conservative Research Department evolved a set of policies based on accepting the main reforms of Attlee’s Labour government, such as the foundation of the NHS. After 1979, and particularly following Britain’s victory in the Falklands War and her defeat of the ‘wets’, Margaret Thatcher evolved a different set of policies that redefined the Conservative Party. And in the period before the 2010 election, David Cameron, with his ‘hug a hoody’ strategy, succeeded in changing his party’s orientation without stirring up enormous intra-party conflict. His three immediate predecessors had utterly failed to do this and had gone down to bad defeats.

Diamond and Radice’s central insight was a key driver within the Labour Party during the period of Neil Kinnock’s leadership. There were plenty of divisions as the party strove to find a strategy which could bring political success, but I would say that these were necessary. The launching of the policy review process and the creation of the National Policy Forum were efforts to replace the ‘OK Corral’ party conference showdowns with less conflictual ways of updating policy. We were clear that unity, however desirable, should not override the imperative of establishing a viable strategy for winning elections. The only issue was how fast to move.

The final chapter of Labour’s Civil Wars identifies a series of challenges that Labour needs to overcome: for example, in relation to Scotland and workers’ rights. But the key is earning a reputation for economic competence. From its foundation, Labour has only been able credibly to assert that it is the most economically competent political party for a brief period, from about 1996 to 2008. Unfortunately, after 2010 we casually threw away that reputation. Unless Labour is ready to ‘compromise with the electorate’ – as many activists argue we should never do! – the party will not win long-term political power. We must test our approaches against the real-life experiences of millions of people and never just claim that we know best.

Unfortunately, in his book The Starmer Project, Oliver Eagleton, following Corbyn’s lead, does not accept this fundamental point. As a result, he fails to address the difficulties and challenging dilemmas that are analysed by Diamond and Radice and faced by every opposition leader, including Keir Starmer. The book’s subtitle, ‘A Journey to the Right’, gives the game away. Eagleton simply throws vitriol at Starmer in an attempt to discredit him. He is unconcerned with the real political challenges Starmer faces.

So there is no illumination of Starmer’s approach to winning the Labour leadership or, once he had become leader, trying to win substantive political power. The author is so steeped in his admiration of Corbyn, despite the manifest failures of his leadership, that he is unable to offer any assessment of the qualities that Starmer brings to the challenges that face the Labour Party. In short, Eagleton’s book tells us nothing of interest, which is a shame, since we are living at a time of great political interest.