Often overshadowed by China's remarkable rise as an industrial power during the past decade, India too has seen dramatic increase in wealth as well as prominence on the world stage.

During the next decade and a half, India's middle class is expected to grow from 5 percent of the population to 41 percent, an increase of 583 million people. During the 20 years prior to 2005, real average household disposable income in India doubled to more than 100,000 rupees. Even with such big jumps in income—about U.S. $2,000 per household—disposable income in India represents only a fraction of that in the United States and other developed nations, even accounting for price differences. Most rural homes lack an indoor latrine, and even in cities fewer than half of Indian homes have a flush toilet. Cars, computers, and refrigerators remain unattainable luxuries for all but the wealthiest of India's population.

Still, recent Indian economic gains may be relatively resilient even in the face of the global economic slowdown. The credit must go to India's aspiring middle class, which has created a robust internal market for Indian goods. These would-be consumers are less reliant on failing global markets for their incomes than their equivalents in China. Their means remain modest by world standards, but their power in the Indian economy is impressive—and helps to account for one of this year's fastest growing economies.

The poor have always outnumbered the wealthy, and we should be glad for every human who has enough to eat today, who might have gone hungry before. This is certainly true in India, where much progress has been made but much remains to be achieved in bringing the benefits of economic development to a vast and growing population. But we must also bear in mind that our planet is simply not as vast as our appetites. If India continues to grow in both population and in wealth, as expected, the strains on natural environment and human infrastructure will be unprecedented. Success in the future will mean finding ways to do more good for humanity with less impact on the Earth. In the coming decades, no nation will have to learn that lesson quicker or more fully than India.