On February 2, 37 U.S. Senators signed a letter to Secretary of State Hillary Clinton seeking information about the Obama Administration’s reported plans to join the European Union Code of Conduct for Outer Space Activities. The letter is a step in the right direction for the Senate, which needs to guard against international agreements that could undermine U.S. national security.

Specifically, the letter reminds the Secretary that Section 1251 of the National Defense Authorization Act for fiscal 2010 expresses concern about the possible negative consequences for U.S. security resulting from space arms control initiatives by keeping limits on space capabilities out of the U.S.–Russian New START arms control treaty. The letter poses a series of important questions about the possible effects of the Code of Conduct, as an arms control agreement.

However, interested Senators need to focus on an additional procedural issue and two substantive issues that are not directly addressed in the letter.

First, if the Obama Administration joins the Code of Conduct, as a non-treaty agreement it will violate the law. Section 2573 of Title 22 of the U.S. Code prohibits the Administration from taking any action, including entering into non-treaty agreements, that limit the armed forces of the U.S. in a militarily significant manner. Accordingly, any agreement that limits U.S. military operations—such as will reportedly be the case with the Code of Conduct—is an arms control agreement and is subject to the relevant provision in the law requiring that the agreement be drafted as a treaty and made subject to the Senate’s advice and consent process prior to ratification and entry into force.

Second, there is a substantive question about how the negotiations on the code of conduct are structured. By focusing on limiting military operations, the Code of Conduct blurs the distinction between arms control agreements on the one hand and law of war agreements on the other. Arms control agreements are about limiting the quality or quantity of arms in peace time. Law of war treaties are about defining permitted and prohibited actions in the conduct of war.

This is not a trifling distinction for military commanders. They can be put in jeopardy of prosecution for violating the laws of war. Accordingly, a future military commander who has to make a split-second decision in the conduct of a space operation that could generate space debris may face a war crime charge if the Code of Conduct, following its entry into force, is deemed to be a law of war agreement.

Third, the European nations that are party to the Code of Conduct are allies and friends of the U.S. It is axiomatic that there is no need to negotiate arms limitation agreements with allies and friends. The chief threats to the U.S. regarding space are China and Russia. It is clear that in negotiating with the European Union, the Obama Administration will make the Europeans surrogates for China and Russia precisely because the Europeans are not seen as a threat to U.S. interests. As a practical matter, a code of conduct with European nations that limits U.S. military space operations will do so across the board. Neither China nor Russia will be bound by the Code of Conduct, but the U.S. will be by its obligations to the Europeans. In this context, the Code of Conduct will be a one-sided agreement that provides a direct advantage to China and Russia.