Japan's Aging Population

Regarding the possibility of a devastating Tokyo earthquake, Vaclav Smil writes,

"[T]he challenge of coping with its consequences would be even greater 20 to 25 years from now, when Japan will be a truly geriatric country. By 2035, Japan will have more people older than 70 years (about 29 million) than people in the prime of their lives, between 20 to 44 years of age. How would such a society cope with the devastation of its capital, largest city, and center of economic, cultural, and educational life?"

Forget about coping with an earthquake - how will they cope with that elderly population?