Congressional Budget Office Cost Estimate: S.J. Res. 10, a Joint Resolution to Repeal the Authorizations for Use of Military Force Against Iraq, and for Other Purposes [open pdf - 161KB]
This is the Congressional Budget Office (CBO) Cost Estimate as reported by the Senate Committee on Foreign Relations on August 4, 2021. From the Document: "S.J. Res. 10 would repeal the statutory authorizations for U.S. military operations against Iraq. [...] S.J. Res 10 would repeal Public Law 102-1, which authorized the President to use U.S. Armed Forces to enforce U.N. Security Council resolutions regarding the 1991 Iraqi invasion of Kuwait. [...] S.J. Res. 10 also would repeal Public Law 107-243, which in 2002 authorized the President to use U.S. Armed Forces to defend the United States against the threat posed by Iraq and to enforce all relevant U.N. Security Council resolutions regarding Iraq. The current Administration has stated that ongoing military operations in Iraq no longer rely solely on the legal basis of P.L. 107-243. Rather, the Department of Defense has asserted that operations to protect U.S. Armed Forces in a combat theater are justified under Article II of the Constitution. Additionally, the department has stated that Article 51 of the U.N. Charter provides the right of self-defense to member nations involved in ongoing military operations. On the basis of that information, CBO estimates that repealing the authorizing legislation would not affect spending to support current military operations in Iraq; thus, enacting the joint resolution would not affect the federal budget."
Congressional Budget Office: http://www.cbo.gov/