朝日新聞に掲載された以下の記事の WikiLeaks 側の文書を確認してみた。
The second was a U.S. request that the Preamble delete reference to the approximately one billion dollar military road on Guam. This road was included during the April 2006 negotiations on cost-sharing as a way to increase the overall cost estimate (i.e., the denominator) and thereby reduce the share of total costs borne by Japan. During the negotiations over the IA Preamble language, the U.S. clarified that the United States would not consider the road an absolute prerequisite for the completion of the Relocation. The Japanese side acknowledged both points, but strongly resisted any language that differed from existing public formulations out of concern that changes would draw Diet scrutiny that would distract from focus on the key issues in the IA. Having registered these clarifications, and obtained satisfactory corresponding Japanese acknowledgment, the U.S. side acceded to the Japanese request to adhere to existing Roadmap language.
The number 8,000 refers to authorized positions in the units identified in the AIPs as relocating to Guam. The number 9,000 dependents is based on a calculation of the number of dependents associated with such units if manned in full. In the context of drafting the 2006 Roadmap, both the 8,000 and the 9,000 numbers were deliberately maximized to optimize political value in Japan, but the two sides knew that these numbers differed significantly from actual Marines and dependents assigned to units in Okinawa. To clarify the balance, the AIP also identifies that 10,000 Marines will remain on Okinawa, and lists the units associated with those 10,000 Marines. In 2004-2006, when the Roadmap was negotiated, the number of Marines assigned to the units in Okinawa was on the order of 13,000, significantly less than the 18,000 authorized.