Reagan cut expenses by eliminating costly and little-used routes and forcing railroads that carried the mail to reduce their rates. Despite the problems the war caused, his department managed to turn a profit, "the only post office department in American history to pay its own way," wrote William C. Davis. Reagan was the only member of the cabinet to oppose Robert E. Lee's offensive into Pennsylvania in June–July 1863. He instead supported a proposal to detach the First Corps of the Army of Northern Virginia to reinforce Joseph E. Johnston in Mississippi, in order to break the Siege of Vicksburg. Historian Shelby Foote noted that, as the only Cabinet member from west of the Mississippi, Reagan was acutely aware of the critical consequences of Vicksburg's capture and control of the river by Union forces.