In his latest letter to JPMorgan (JPM) shareholders, CEO Jamie Dimon hits a hot button issue of the day: trade policy. And, more broadly, America’s role in the global economy.

“America’s role in the world is critical,” Dimon writes. “Reversing the interconnectedness built by our post-World War II institutions is neither desirable nor feasible. As a nation, we cannot isolate ourselves any more than we can stem the ocean’s tide. The international system provides agreed-upon rules of the road — and mechanisms for enforcing them.”

Adding, “At this moment of uncertainty, however, U.S. global engagement is needed more than ever.”

Dimon did, however, say that the United States’ trade relationship with China is “far more complex” than its agreements under NAFTA, adding that “the complaints are more legitimate.”

Specifically, Dimon highlights that China considers itself a “developing” nation that ought not be subject to the same WTO standards as the U.S. despite being the world’s second-largest economy and home to 20% of Fortune 500 companies.

On Wednesday, China announced that it would impose tariffs on $50 billion worth of U.S. imports, including airplanes and soybeans, which pressured global markets early in the day before a big rebound. Earlier this week, the Trump administration unveiled a 1,300-item list of Chinese goods that would be subject to tariffs.

Both U.S. and Chinese government officials, however, have stressed that these tariffs have not yet been put in place and that potential negotiations on new trade agreements remain in play.

Dimon writes that, “anything that starts to resemble a trade war creates risk and uncertainty to the global economic system.” And while he says a better relationship with China on trade is possible, there is “a chance that miscalculations on the part of the various actors could lead to negative outcomes.”

“This obviously creates higher risk and more uncertainty until resolved.”

More with Jamie Dimon:

• JPMorgan’s Jamie Dimon talks China, trade and immigration in his annual letter

• JPMorgan’s Jamie Dimon says the 10-year ‘could or should’ trade at 4%

• DIMON: Immigration reform is ‘tearing apart’ U.S. society and holding back the economy

• DIMON: The $1 trillion that tax reform adds to the deficit is not a material number

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Myles Udland is a writer at Yahoo Finance. Follow him on Twitter @MylesUdland

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