President Donald Trump's proposal to rename the United States Department of Defense to the Department of War could cost approximately $125 million, according to an estimate by the Congressional Budget Office (CBO). The potential rebranding stems from an executive order signed on September 5, which aimed to reinstate the historical titles of "Department of War" and "Office of the Secretary of War" as secondary designations for the current Department of Defense and the Office of the Secretary of Defense.

The executive order included a provision for the Secretary of War to submit a formal application for a permanent name change. Senators Jeff Merkley and Chuck Schumer requested the CBO analysis. The CBO estimated that a minimal implementation of the name change, primarily affecting internal departmental operations, would cost around $10 million. This initial cost, the CBO noted, could be absorbed within the department's existing budget as an opportunity cost. However, a comprehensive rebranding, encompassing all aspects of the department's operations, could escalate costs to $125 million. This figure accounts for expenses such as replacing stationery, signage, and updating official documents across the department.

The Department of Defense, established in 1947 as part of the National Security Act, consolidated the War and Navy Departments. The original Department of War was created in 1789 and was initially responsible for the operation and maintenance of the United States Army, also handling naval affairs until the establishment of the Department of the Navy in 1798. The proposed name change evokes a historical period when the United States' global role was significantly different.

The potential renaming has sparked debate, with some critics arguing that the "Department of War" title could project an aggressive image internationally, potentially impacting diplomatic relations and alliances. Others suggest that the funds allocated for the rebranding could be better utilized in other critical areas, such as military readiness or supporting veterans' programs. The CBO's cost estimate highlights the financial implications of the proposed change, raising questions about the priorities and rationale behind the initiative. The next step involves the Secretary of War submitting the application for the permanent name change, after which the proposal would likely face further scrutiny and debate within the U.S. government.