Stocks are selling off on Friday after a mixed August jobs report raised concerns about when the Fed will hike interest rates.
But Fed action is not the only thing investors should keep an eye on during this period of market volatility.
Bruce McCain, chief investment strategist at Key Private Bank, tells CNBC's "Power Lunch" he's concerned about a possible trade war.
"If trade volumes can increase, the pressure on China and the rest of the world would be reduced. If trade continues to struggle, however, the problems in China are more likely [to] intensify and would also stand a better chance of spilling into other parts of the world. If trade continues to founder, there would be a greater risk of trade wars," McCain said.
Another risk for McCain is business sales, which could determine the market's direction in the near future.
"Business sales have slowed faster than inventories for much of the past year, which remains an overhang on production. Part of this undoubtedly incorporates the slowdown in international trade we have seen over the course of the first half of this year and the pressure U.S. producers are experiencing because of the stronger dollar," McCain said.
He believes stronger consumer spending may be the best hope for reducing this trend.