Lenin was the brilliant strategist of the socialist revolution. Substantiate.

Lenin's claim to strategic brilliance rests on a consistent pattern — absolute fixity about the goal, and complete willingness to change the route.

• The party as instrument. What Is To Be Done? (1902) argued that workers left to themselves reach only trade union consciousness, and that revolution requires a disciplined vanguard of professional revolutionaries. The split with the Mensheviks in 1903 was over this, and it gave him in 1917 the one thing his rivals lacked: an organisation that could act on a decision.

• Relocating the revolution. Imperialism, the Highest Stage of Capitalism (1916) argued that capitalism had become a world system, so revolution would break not at its most developed point, as orthodox Marxism expected, but at its weakest link. That single move made backward Russia a legitimate site of proletarian revolution.

• The April Theses. Returning in April 1917, he refused all support to the Provisional Government at a moment when his own party leadership favoured cooperation, and demanded all power to the Soviets. The slogan Peace, Land and Bread bound three constituencies — soldiers, peasants and workers — to one programme, and it was the only programme addressing the war.

• Timing the insurrection. He judged that October, before the Constituent Assembly and while the Bolsheviks held majorities in the Petrograd and Moscow Soviets, was the moment; he overruled Zinoviev and Kamenev, and seized power in the Soviets' name rather than the party's.

• Knowing when to retreat. Brest-Litovsk in March 1918 surrendered enormous territory to save the regime — space traded for time — against near-unanimous opposition. The New Economic Policy of 1921, restoring private trade after the failure of War Communism, was the same judgement applied to economics.

Assessment. He was not a strategist of grand design but of the concrete moment, and his weaknesses were the reverse of his strengths — the disciplined vanguard became a one-party state, and the tactic of dispersing the Constituent Assembly in January 1918 set the pattern that Stalin inherited.