The numbers are certainly sobering. All told, developing- nation currencies have fallen to their lowest levels since 1999, and bonds denominated in those currencies have wiped out five years’ worth of gains.

Equity Divergence

Meantime, in the stock market, the emerging world and developed one are diverging sharply. Since 2009, the MSCI index has fallen 10 percent while developed markets have soared about 50 percent. Based on estimated price-to-earnings ratios, the emerging markets are trading at their biggest discount to developed ones since 2006 -- 31 percent.

The good news is that few strategists foresee full-blown crises like the ones that shook East Asia in the late 1990s or Latin America in the early 1980s.

Yet a confluence of powerful forces -- notably a strong dollar, weak commodities prices, China’s slowdown and higher U.S. rates -- will, at minimum, bridle growth.

Emerging Trouble

For much of the past 15 years, easy credit from the Fed and a robust Chinese economy combined to drive investment dollars into emerging markets and power growth. Now, the risk is that the twin “suns” of the Fed and China will become out of sync, as the U.S. starts raising rates and the Chinese economy slows, according to Stephen Jen, co-founder of London-based SLJ Macro Partners LLP and a former International Monetary Fund economist.

If that happens, as SLJ predicts, there will be more trouble for emerging markets, Jen wrote in a July 23 note to clients.

Even as China cools, its exporters are grabbing market share from competitors elsewhere, including those in other emerging economies, according to David Lubin, an economist at Citigroup Inc. At the same time, Chinese manufacturers are increasingly procuring components at home, rather than importing them. Both developments are bad news for other emerging economies. Excluding China, growth in developing countries was virtually flat during the second quarter.

The IMF still expects the world’s emerging economies to grow 4.2 percent this year, even as Brazil and Russia sink into recession. But that’s only 0.9 percentage points faster than the world economy as a whole, the smallest gap since 1999.