In June 2007, tensions are running high between China, North Korea, South Korea, and Japan, due to Japan's formation of an Information Self Defense Force (I-SDF). Considering this to be a violation of Article 9 of the post-World War II Constitution, and blaming the I-SDF for information warfare attacks against their countries, Chinese and North Korean forces establish a blockade in the Yellow Sea against Japanese shipping. As Japan is an ally of the United States, and thus the NSA's Third Echelon, the US Navy dispatches a highly advanced warship, the USS Clarence E. Walsh (CG-80), to the Yellow Sea with the hopes that China and North Korea will back down at its presence.