Japan and India are natural allies whose fast-growing relationship is remarkably free of any strategic dissonance. So, Indian Prime Minister Manmohan Singh's Tokyo visit this week stands in sharp contrast to Chinese Premier Li Keqiang's just concluded India tour, which, behind the hype, helped to underscore the deep Sino-Indian divide.

India, China and Japan, constituting Asia's pivotal triangle, are transforming relations among themselves in a way that portends growing strategic collaboration between New Delhi and Tokyo but sharper geopolitical competition between China and the other two Asian powers.

The Sino-Indian relationship was recently disturbed by a stealthy incursion across the disputed Himalayan border by the People's Liberation Army, which pulled back its troops just in time to allow Li to go ahead with a scheduled visit to India. The visit helped shine a spotlight on a negative aspect extending beyond the Himalayan tensions — India's ballooning trade deficit with Beijing, compounded by China's import of mainly primary commodities while exporting finished products. A flood of cheap Chinese goods has undercut Indian manufacturing.