The main talking point of President Barack Obama’s visit to Japan on 23-24 April has been his declaration that the Senkaku/Diaoyu Islands are subject to Article 5 of the Japan-US Security Treaty. Article 5 of the treaty states the two states would act against an attack on “territories under the administration of Japan.” This is an important development in US-Japan security relations, as Obama became the first sitting US president to make this coverage explicit and perhaps even challenge the traditional US position of not taking sides in territorial disputes.