Margie Siegal has been covering the motorcycle scene since the late 1980s and has written for a number of magazines. She is also the author of "Harley-Davidson: A History of the World's Most Famous Motorcycle." She is working on a second book about Harley-Davidson. The views expressed in the commentary are her own.

(CNN) Harley-Davidson -- and, really, the American motorcycle industry -- is in many ways iconic of America. Motorcycles are symbolic ambassadors for the American spirit. At the same time, the industry, which employs many people in both manufacturing and retail, runs on a very thin profit margin. Cutting into that profit margin does not help the motorcycle industry, motorcyclists or the American economy in general.

Margie Siegal

Recently, the Trump administration raised tariffs on some European products, which, predictably, led to something of a trade war. The European Union came up with its own tariffs -- including higher duties on American-built motorcycles -- that will add an estimated $2,200 to the price of Harley-Davidson motorcycles exported to the EU.

This is not the first time in recent history that trade problems that have little to do with the motorcycle industry have affected motorcyclists. In late 2016, when American farmers trying to export beef to Europe ran into difficulties, federal authorities proposed imposing tariffs on European off-road motorcycles.

American factories do not build any equivalent to these dirt bikes, and raising the prices on them would have directly affected American dealers, American manufacturers of accessories and the American families who buy and use these bikes. Luckily, the idea fizzled.

Now, however, the American motorcycle industry could be in real trouble. Raising the tariffs on Harleys sold in Europe forces Harley to make a business decision: either to raise prices or to move production overseas, both of which could elicit blowback from the company's core customers.

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