Congressional Budget Office Cost Estimate: H.R. 4547, Cost of War Against Terrorism Authorization Act of 2002 [open pdf - 22KB]
From the Summary: "H.R. 4547 would authorize appropriations totaling $10 billion for fiscal year 2003 for the Department of Defense (DoD) for the conduct of operations in continuation of the war on terrorism. It also contains several provisions that would affect military compensation and that would establish additional teams within the Army National Guard to provide support to civil authorities in the event of an attack involving a weapon of mass destruction. CBO [Congressional Budget Office] estimates that appropriation of the authorized amounts for 2003 would result in additional outlays of $9.9 billion over the 2003-2007 period. The bill also contains provisions that would raise the costs of discretionary defense programs over the 2004-2007 period. CBO estimates that those provisions would require additional appropriations of $965 million over those four years.'"
Congressional Budget Office: https://www.cbo.gov/