Amid concerns about sagging growth in both advanced and developing economies, Japan — which is heavily dependent on Asian demand — may take heart from the region's potential to drive a global revival.

For centuries, less than 1 percent of the world's population had sufficient income to spend on anything more than basic daily needs. But McKinsey consultants say a series of trends over the past two decades have powered growth in emerging economies, led by Asia, and more than doubled the ranks of the consuming class, to 2.4 billion people.

The trends include rapid urbanization, removal of trade barriers, integration of peripheral nations into the global economy, and the spread of market-oriented policies.