Encouraged by U.S. growth and the prospect of higher interest rates, investors have sent the dollar surging-a welcome development after years of decline on the heels of loose Federal Reserve monetary policy. It’s also made it more affordable for Americans to pack their bags and travel the world.

But the renewed power of the dollar may wind up hurting the U.S. economy. A soaring currency-the U.S. Dollar Index (Exchange:.DXY) spiked to its highest in 12 years this week-isn’t necessarily good for trade or manufacturers. The greenback’s sudden strength is disruptive to U.S. exports, and companies that rely on sales abroad.

To be certain, the strong dollar is beneficial to the U.S. economy in many respects, by restraining inflation and making foreign goods cheaper for American buyers. It’s also a reflection of an economic outlook that is far brighter than other major developed economies, many of which are either growing sluggishly or flirting with outright recession.

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Yet conversely, a pricier dollar also makes it more expensive for foreign countries to buy U.S. products. That impact is already being felt: November numbers from the Commerce Department showed exports dipping from the previous month.

The sinking euro (Exchange:EUR=), which is hovering at its lowest level in nearly a decade, helped send exports to the European Union plunging by 7.7 percent. Meanwhile, exports to China slipped 3.9 percent.

American-based manufacturing companies have already begun revising down their earnings in anticipation of the currency tailwinds. In a 2015 outlook meeting, 3M (MMM)Senior Vice President Nick Gangestad said the company expects to reduce earnings per share by 10 cents to 20 cents based on a stronger dollar.

Manufacturers have already begun to gripe. Across the industry, data from the first nine months of last year saw 2.2 percent growth in manufactured goods exports, slower than in comparison to 2013, according to Chad Moutray, chief economist with the National Association of Manufacturers.

“We continue to see relatively sluggish growth overall for manufactured exports,” Moutray said, citing trade to both Europe and Japan-where the yen is also sitting near a multiyear low against the greenback-as troublesome developments.

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“If you’re a manufacturer in the U.S. competing against a manufacturer in Europe and you’re competing on price, certainly the strong dollar won’t help there,” he added.

Globalized companies with exposure to economic risks abroad are particularly harmed by a strengthening dollar, because their sales abroad need to be converted back into dollars for reporting purposes.

“You can see multinational corporations are seeing more pressure,” said Richard Hastings, macro strategist at Global Hunter Securities.

McDonald’s (MCD), for one, has revised down its expectations for earnings per share, while General Mills (GIS) has already attributed currency headwinds to reductions in its fiscal 2015 earnings per share. Nike (NKE), Costco (COST) and ConAgra Foods (CAG) all said recently that overseas revenue has been crimped by a stronger dollar.

Economic concerns in Europe, combined with a slowdown in China, are also contributing to a slowdown. That may erode earnings expectations for multinational companies in 2015.

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“The EU is the biggest economic unit in the world,” Hastings said. “With growth so slow and the euro/ dollar rate so unstable, it speaks to the risk of mid- to long-cap stocks engaging in cross border trade.”

With exports weakening, it might seem like U.S. companies should gear up for a rough 2015. But Marc Chandler, global head of currency strategy at Brown Brothers Harriman, said companies are likely to compensate for weaker sales abroad with stronger sales at home.

“The U.S. is not export led. The U.S. economy is about buying locally and selling locally,” Chandler said. Using the dollar’s exchange rate’s fluctuations “is not the best way to look at it,” he added.

In a press conference Thursday, General Motors (GM) CEO Mary Barra said the stronger dollar comes with the local opportunity to make money, even as she acknowledged the exchange rate is a challenge to international sales.

“In some cases it’s a positive, in some it’s a negative,” Barra said. “I think we continue to want to have our production balanced where we build where we sell and have the right amount of localization.”

Others agreed and saw optimism for American companies through domestic demand.

“I think we will continue to see relatively strong demand from consumers as well as investments. I see pretty strong business and consumer spending continuing to lift the economy,” Moutray said.