THE COSTS of the Edward Snowden affair continue to mount for the Obama administration — though so far the visible damage is primarily political, rather than national security-related. On Monday, President Obama and Secretary of State John F. Kerry struggled to respond to new allegations, leaked by Mr. Snowden to the German magazine Der Spiegel, that the National Security Agency (NSA) has bugged European Union offices in Washington and New York. If true — and Mr. Obama did not offer a denial — the revelation could complicate the incipient U.S.-E.U. free-trade talks and further sour Europeans’ once-soaring regard for Mr. Obama. Governments and their intelligence services, aware that allies often spy on each other, may be less perturbed....

In fact, the first U.S. priority should be to prevent Mr. Snowden from leaking information that harms efforts to fight terrorism and conduct legitimate intelligence operations. Documents published so far by news organizations have shed useful light on some NSA programs and raised questions that deserve debate, such as whether a government agency should build a database of Americans’ phone records. But Mr. Snowden is reported to have stolen many more documents, encrypted copies of which may have been given to allies such as the WikiLeaks organization.

...The law is absolutely clear. It states: “Whoever knowingly and willfully communicates, furnishes, transmits, or otherwise makes available to an unauthorized person, or publishes , or uses in any manner prejudicial to the safety or interest of the United States or for the benefit of any foreign government to the detriment of the United States any classified information— (1) concerning the nature, preparation, or use of any code, cipher, or cryptographic system of the United States or any foreign government; or (2) concerning the design, construction, use, maintenance, or repair of any device, apparatus, or appliance used or prepared or planned for use by the United States or any foreign government for cryptographic or communication intelligence purposes; or (3) concerning the communication intelligence activities of the United States or any foreign government; or (4) obtained by the processes of communication intelligence from the communications of any foreign government, knowing the same to have been obtained by such processes— Shall be fined under this title or imprisoned not more than ten years, or both.”

Note that emphasis, which I added: The law specifically states that publishing, not just divulging, such information is a federal crime. Greenwald clearly violated this law (as did The Post, for that matter, when it published classified details of the NSA’s PRISM program)....