If this key trend ends, stocks could be in trouble

In 2015, small is beautiful
In 2015, small is beautiful   

It could be called the Great American Dichotomy: As the rest of the world struggles, the American economy continues to slowly grow. But some traders say that investors are making a big mistake if they think this divergence will continue forever.

After Caterpillar released earnings Thursday, CEO Doug Oberhelman told CNBC's "Squawk Box": "We've seen a real dichotomy here in the world. The U.S. growing fairly slowly but growing steadily, and everywhere else, there's not much good news outside the U.S. China is down significantly year over year. Brazil is weak economically. And Europe is still kind of flat but in our case down year over year."

The dichotomy is certainly confirmed in the latest economic numbers. Markit's flash Purchasing Manufacturing Index for the euro zone fell to 53.5 for April, weaker than the March reading and below forecasts. Japan's flash PMI showed that manufacturing activity declined this month. The China flash PMI number compiled by HSBC similarly showed an April contraction and hit a one-year low. Meanwhile, U.S. PMI for April came in at 54.2, below expectations but still showing growth.

"It's very true to say that the world economy as a whole is much slower than the policymakers would have liked to see at this point," said Boris Schlossberg, a currency strategist with BK Asset Management.

"For the time being, I think the U.S. consumer still remains relatively buoyant. And as long as we can maintain this slow but steady pace, we may be able to work our way out of it for the time being," he said. "But I think markets have clearly priced in a far more benign scenario than what we're seeing on the data front."

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Gina Sanchez, CEO of asset allocation firm Chantico Global, is of a similar mind.

"The U.S. growth story is weaker than we think. And when you dig into the numbers, demand has been improving, but very, very slowly. And U.S. equity markets have priced in much more than that," she said.

Sanchez believes the transmission mechanism between a weak global economy and U.S. shares will be the surging U.S. dollar, which is weighing on the first-quarter earnings of many of multinational corporations.

Dollar strength will be "the great equalizer for the global scenario. And so I do think that that's going to hit earnings at some point, and U.S. equity markets will have to come off," she said.

The dichotomy "cannot continue," Sanchez said.

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