"China seems to be the lead story and everything seems to be following," said Art Hogan, market strategist at Wunderlich Securities. "The moves we've seen this year are just so neck breaking,"
"A 10 percent correction doesn't matter. It's a question of how much damage it's done in a very short amount of time," said Hogan.
Markets have been spooked by China's stock market declines, but more so the drop in its currency. The yuan has been losing ground against the dollar since the International Monetary Fund granted it reserve currency status in late November.
The fear is that China will export deflation with the devalued yuan.
"If a bear market means the market is going down 20 percent, I don't think we're going to be down 20 percent this year. Could we be down? Yes. But I think it's more likely we will be down modestly," said Bob Doll, senior portfolio manager and chief equity strategist at Nuveen.
Read MoreMarket sell-off triggers fear of Asian flu again
Doll said the current sell-off is very similar to the China-fed market correction in August, that took the S&P 500 down 11 percent.
The sentiment on China then was "It doesn't know what it's doing. They're having technical issues around the markets. Their currency is falling. There's the unanticipated devaluation. Commodity prices were going down, and people were concerned they weren't able to control it, and the world would be in a deflationary spiral," said Doll.
The China fears have crept back into world markets, as concerns about U.S. economic weakness have increased. Fourth-quarter growth is pegged at just 1 percent by many economists, and the weakness comes at the same time the Fed has started raising rates.
The outlook for U.S. corporate earnings remains weak and deteriorating manufacturing data have raised concerns that there's even more weakness ahead.
Read MoreSources: China wants quick, sharp currency decline
Oil prices have been another nagging worry for stocks, and this week U.S. crude futures plunged 10 percent, touching 2003 lows briefly Thursday.
"I do think this sell-off (in stocks) is warranted. Every risk we worried about is materializing, particularly when it comes to currencies and commodities," said David Bianco, chief U.S. equity strategist at Deutsche Bank.
While he said his earnings forecast is at risk due to collapsing energy prices, he still expects the S&P to reach 2,250 by year-end. "I don't think we go to the August lows." The S&P 500 fell to a low of 1,867 in August.
Read MoreCashin: This is the biggest China concern
"I think there's plenty of earnings risk, but the earnings risk is still concentrated at those same commodity and emerging market-exposed sectors," said Bianco.
Doll expects China to succeed in stabilizing its markets. But the concern is that it's not managing its message well.
"I think China is managing their economy fairly well given the challenges. I think they run into a lot more challenges trying to manage the markets, and they're learning quickly that trying to manage a market is harder than managing an economy," said Bianco.