What country before ever existed a century and half without a rebellion? And what country can preserve it’s liberties if their rulers are not warned from time to time that their people preserve the spirit of resistance? Let them take arms. The remedy is to set them right as to facts, pardon and pacify them. What signify a few lives lost in a century or two? The tree of liberty must be refreshed from time to time with the blood of patriots and tyrants. It is it’s natural manure.

Letter from Thomas Jefferson to William Stephens Smith, November 13, 1787

The hesitancy of the republican government was fatal in a rapidly developing crisis, because the initial uncertainty enforced a defensive mentality. The prime minister did not dare arm the UGT and CNT. He refused to depart from the legal constitution of the state, even though a state attacked by its own ‘spinal column’ has ceased to exist for all practical purposes. The delay in issuing weapons discouraged pre-emptive or counter-offensive moves against the rebel military. ‘The republican authorities were not prepared to give us arms,’ recalled a carpenter from Seville, ‘because they were more afraid of the working class than they were of the army. We communists did not share the government’s confidence that the rising would be suffocated in twenty-four hours.’

They encouraged the idea that ‘to resist was to win’, as a slogan later put it. Even during the rising the communist deputy La Pasionaria had expressed this dangerously appealing idea with ‘No Pasarán! (They shall not pass!)’, her famous plagiarism of Pétain’s phrase at Verdun.

The military plotters seldom had complete surprise on their side, but doubt and confusion were certainly in their favour. If the workers held back on the advice of a civil governor who was afraid of provoking the local garrison into revolt they were lost. They paid for this hesitation with their lives. But if they demonstrated from the beginning that they were prepared to assault the barracks, then most of the paramilitary forces would join them and the garrison surrender.

— “The Battle for Spain” by Anthony Beevor