Congressional Budget Office Cost Estimate: S. J. Res. 21, A Joint Resolution for the Authorization for the Use of Military Force Against the Government of Syria to Respond to Use of Chemical Weapons [open pdf - 32KB]
This is the Congressional Budget Office (CBO) Cost Estimate as ordered reported by the Senate Committee on Foreign Relations on September 4, 2013. From the Document: "S. J. Res. 21 would authorize the President to use military force against the government of Syria, for up to 90 days, in response to its use of chemical weapons. Prior to the use of force, the President would be required to provide a determination to the Congress addressing several criteria to show that such action is necessary and in the national interest. In addition, it would require the President to submit to the Congress a strategy for negotiating a political settlement to the Syrian conflict, a comprehensive review of U.S. policy towards Syria, and periodic reports on the progress of military operations. The Administration has not detailed how it would use the authority that would be provided by this resolution; thus, CBO has no basis for estimating the costs of implementing S. J. Res. 21."
Congressional Budget Office: http://www.cbo.gov/