Prime Ministers, and their rise to power: a thread.

At some point in the career of every PM, there is either a moment, or a combination of factors, which places them in pole position for the leadership later on, although this may only be clear in retrospect.

I propose to try and identify these moments (or factors) in the career of every PM since 1900. Each one is questionable, so I would welcome contention.

Salisbury: the definitive moment would be the Eastern Crisis of 1875-78, & his breach with Derby. Derby, for so long the potential heir to the leadership, was driven out of the party, and S acquired Beaconsfield's confidence and the prestige of the Berlin settlement.

Salisbury's only real competitor after Beaconsfield's death was Northcote, who simply wasn't in his class.

Balfour: his period as Chief Secretary of Ireland after 1887. Yes, his uncle's patronage would have probably paved the way for a tilt at the leadership anyway: but it was his performance here that convinced his colleagues that he was more than an intellectual dilettante.

Campbell-Bannerman: the breach between Rosebery & Harcourt, which began under Gladstone, & became unbridgeable under R's premiership in 1894-95. Once R&H had had their fill of mutual destruction, CB was the only senior figure in the lower House who could offer unity.

Asquith: the Liberal Unionist split (taking away a number of older Liberal legal politicians) and the 1886 defeat allowed the young HHA to flourish in Opposition. When he became Home Sec. in 1892 at 39, that gave him a generational advantage that eventually took him to the top.

Lloyd George: the anti-war crusade in 1899 & his fight against the Education Act gave him the leadership of radicalism. His success at the BoT cemented him in frontline politics. But it took his resolution of the shell crisis to give himTory support in Dec 1916.

Bonar Law: Law's willingness to take on the Liberals on tariff-reform in free-trade Lancashire, his effectiveness in the Commons, combined with the flexibility of his referendum pledge, were all factors in his initial rise to leadership.

His actual assumption of the premiership in 1922 depended on his decision to come out against Austen & the Coalitionists despite the effect on his health; a decision which was greatly influenced by the pressure of close friends like Beaverbrook.

Baldwin: his friendships with JCC Davidson & Sir George Younger mattered. Davidson gave him the entree into ministerial politics; Younger kept him in touch with the Tory backbenches & the party in the country when the other Coalitionists ignored such matters.

It was this latter factor which made his anti-LG intervention so devastating at the Carlton, and enabled him to decapitate the Coalitionists and narrow the Law succession to him & Curzon.

Ramsey MacDonald: even by the mid-1920s, Labour still suffered from a dearth of people who looked like leaders. Only Snowden & Henderson came close as rivals before 1931, and none could have defeated him before then.

Neville Chamberlain: breaking with his brother and entering Law's government in 1922 was a ruthless act, but one which gained him a solid position in the Tory pecking order after that, and where his rivals fell by the wayside over the years.

Churchill: his potential as a future leader was obvious, even at an early stage in his career. I am going to be boring, and take the vindication of his post-Munich stance as the decisive factor.

Attlee: his connection with the East End, dating back to his conversion. Crucially, it gave him a solid base in 1931 when potential rivals had either left the party or were swept out of Parliament.

Eden: he was lucky in the early 1930s to be 2nd to Sir John Simon, and then to benefit from Sir Samuel Hoare's resignation. His own resignation in 1938 gave him a solid national profile which could have taken him to the leadership earlier, had it not been for WSC.

Macmillan: an unlikely successor in some ways, even after Suez. But his flair and skill in dealing with Housing in 1951, an issue where the government was certainly vulnerable, was the first opportunity he had to show that he had the qualities of a leader.

Sir Alec: his performance at the FO from 1960 surprised those who considered him an anachronism, and also (crucially, in the context of 1963) bought him a lot of support from the Tory right. Had Lennox-Boyd been appointed instead, his path would have been much less clear.

Wilson: the 1951 resignation with Bevan. Not only did it buy him crucial credit with the left, but it gave him a solid ballast of parliamentary and activist support. As he was the best tactician amongst the Bevanites, he was also the one who gained most in the long run.

Heath: Macleod's Magic Circle article of 1964. Of the three 'next generation' candidates, Macleod would never be forgiven, and there were always people with Doubts concerning Reggie. That left one man standing in 1965.

Thatcher: her ability to survive the Heath period (and to avoid sacking in 1972). That meant that the credible Right choice in late 1974 could either be her or Joseph, and we all know what Sir Keith did to spoil his chances.

Major: I would go for the 1988 spending round. Not only did he manage the round successfully, but he ended up destroying John Moore's credibility with No. 10 in the process. After Moore, he was the Cabinet minister of his generation who was least tarnished by wetness.

Gah, forgot Callaghan! A very rare case where the 'marker for the future' leadership campaign (in his case, 1963) paid off. Ultimately, he won by being the candidate of the right who retained the greatest credit with the trade unions.

(One interesting Callaghan counterfactual: had Alf Robens stayed in politics, then he could have either had a better chance of being a right unity candidate in 1963 - stopping Callaghan's candidature - or of becoming the big figure on the trade unionist right.)