Sam Hall (story)

The US also has exclusive control of all human settlements in the Solar System; the most important of these is a pre-Mariner habitable Venus, which hosts thorium mines operated by conscript labor under inhumane conditions, though there are also colonies on Mars, the Moon, and the Jovian satellites.

Major Thornberg is a technical officer in command of an underground base built around "Matilda," a vast electromechanical computer that maintains a comprehensive national database of all US citizens' records and interactions.

Unable to obtain any independently verifiable information on Hall, the government begins to suspect internal subversion and grows increasingly paranoid; meanwhile, the rebels emerge into the open and launch a full-scale civil war, billed as the "Third American Revolution."

Thornberg takes advantage of the worsening chaos by inserting incriminating fabrications into the records of senior regime personnel, hoping to sow distrust among the ranks and bring down the government before it can recall its Venusian garrison troops — which include his son — to reinforce Earth.

In an epilogue, Thornberg asks a rebel officer what will be done with Matilda; the man assures him it will be destroyed once the war ends, as the underground believes that a government with the ability to conduct this level of surveillance against its population is incompatible with democracy.