When Shinzo Abe, Japan's prime minister, addressed graduating cadets at the country's National Defence Academy this month he made clear they were entering the military at a time of transition.

Facing them, he said, were "various challenging problems" ranging from North Korea's nuclear development to "the proliferation of weapons of mass destruction". A commitment by Japan to playing a more active role in international affairs would also inevitably lead to further dispatches of troops and equipment to hot spots around the world.