Grant reorganizes the Union command at Chattanooga

Grant arrived with authority to assess Rosecrans and chose Thomas because he believed Thomas would acknowledge the new chain of command. Reports that Rosecrans might abandon Chattanooga were false, but Grant's order to hold the city drew Thomas's firm promise to remain until the army starved. Sherman brought aggression and an intuitive working relationship with Grant. Thomas supplied steadiness and professional competence, while Hooker was talented but intensely sensitive about recognition. Hooker's later dispute over the praise given to Sherman cost the army an officer considered especially capable with cavalry. Operational command depended on matching these strengths, judging imperfect information, and managing personalities.