So much depends on China and the ability of its economy to escape a hard landing that crushes growth.

This may be the biggest immediate legacy of the eurozone debt crisis. With the eurozone projected to grow by just 0.7% -- or less -- next year and the U.S. economy projected to chug along at 2% growth or less, China will be the make-or-break story for a huge number of companies in 2012.

Investors are used to this by now for the shares of companies like Freeport-McMoRan Copper & Gold (FCX, news), Vale (VALE, news)or Peabody Energy (BTU, news). Worries that growth in China might be slowing mean lower share prices for companies that supply the commodities that feed China's manufacturing machine. When growth looks stronger than expected, these shares climb.

But China's influence has been growing. It now extends well outside the commodity and materials sectors to stocks that don't immediately seem to have a China connection. The China risk in many of these stocks isn't well recognized by investors. And I'd argue that risk is likely to be especially high over the next six months or so because of the way that many of these stocks are increasingly dependent on China for growth.

I call this the Tiffany (TIF, news)problem.

On Nov. 29, before the New York market opened, the high-end luxury retailer announced third-quarter earnings for the fiscal year that ends on Jan. 31 that beat Wall Street estimates by 10 cents a share. But the stock plunged 11.2% from the Nov. 28 close to the Nov. 29 open.

The reason? The company announced disappointing guidance for the fourth quarter and for the full fiscal year.

Global net sales would climb by a percentage in the high teens for the full year, Tiffany told investors and analysts. But sales would increase by just a low-teens percentage in the fourth quarter. That's significant growth, but it's disappointing after a 20% increase in worldwide sales in the first half of the year. And that, of course, explains the sell-off.

But what interests me is the regional composition of the company's sales guidance. In the fourth quarter, Tiffany expects sales to slow in the Northeastern U.S. and in Europe. For the full year, that doesn't have a big effect on projections for sales growth in Europe and the United States. In its full-year guidance, Tiffany kept sales growth projections unchanged at 20% for Europe and in the high teens for the United States.

The only region where Tiffany is projecting an increase in sales from its last guidance is the Asia-Pacific region. In that region, dominated by China's economy (especially since Tiffany breaks out Japan as a separate region), the company has raised its projections for growth to 35% for the year from earlier guidance of 30%.

Think about that for a minute or two. Here's a company saying that it expects sales growth to accelerate from the region dominated by China at a time when China's growth, which has dropped to an annual 9.1% in the third quarter from 9.5% in the second quarter and 9.7% in the first quarter, is expected to slow further. And here's a company that delivered disappointing guidance on growth for the fourth quarter ratcheting up its projections for that quarter's growth from the region where growth is slowing.

I'm not saying that Tiffany won't make or beat its latest projections. But I am saying that uncertainties about growth in China increase the risk in this stock and others such as Coach (COH, news)-- a member of my Jubak's Picks portfolio -- that are counting on growth from China to make up for slowing growth in Europe and the United States.

I'd break down that China risk for Tiffany and similar consumer companies that need growth in China into two parts.

Can China soften a hard landing?

First, there's the risk these companies share with commodity and materials companies: China's efforts to slow its economy in order to fight inflation might just have worked too well.

Last week, the HSBC flash purchasing managers index showed a drop to 48 in November from 51 in October. (Anything below 50 signals a contraction.) The drop took the index down to the lows of April 2009, when China's economy was still struggling to throw off the effects of the global financial crisis. That PMI reading suggests that industrial output is likely to fall to 11% to 12% annual growth in the last quarter of the year. That would be the slowest since 2009. Export growth hit an eight-month low in October. Housing prices moved lower in October for the first time in 2011.