Defense Secretary Ashton Carter confirmed on Tuesday that the Lassen, a U.S. Navy guided missile destroyer, traveled Monday within 12 miles of the Subi Reef, which was underwater until the Chinese government built it into an artificial island. Under questioning from the Senate Armed Services Committee, Carter said the U.S. has the right to operate near the Chinese structures. He expressed support for doing such a “freedom of navigation operation” again.

“What you read in the newspaper is accurate, but I don’t want to say when, whether or how we operate anywhere in the world,” he said. “These are operations that we should be conducting normally.”

Carter has publicly asserted U.S. access to these waters since his speech in May at the Shangri-La Dialogue in Singapore. Admiral Harry Harris, the head of Pacific Command, has advocated that right as well, within the administration. But other senior officials pushed to delay the sail-by, fearing it would provoke Beijing and hurt other areas of cooperation, U.S. officials told me.