What is the dollar smile theory in simple terms?

The dollar smile theory says the U.S. dollar strengthens in two very different moments: when the world panics, and when the U.S. economy is beating everyone else. Investors buy dollars for safety during crises, then buy them again to chase American growth during a boom. The dollar mostly weakens in between, when global growth feels calm and steady.

Who came up with the dollar smile theory?

Stephen Jen, a former IMF and Morgan Stanley economist, developed the dollar smile theory in the early 2000s. He now runs the hedge fund Eurizon SLJ Capital. His framework explains why the dollar rallies at both ends of the economic cycle, crisis and boom, while drifting lower during the calmer stretch in between.

Why did the dollar rally during the 2026 Iran war?

Fear drove it. When U.S. and Israeli forces struck Iran, investors dumped stocks, gold, and bonds and rushed into dollars for safety. Oil prices spiked too, and since oil is priced in dollars, that alone increases global demand for them. Both forces hit at once, giving the dollar its biggest two-day rally in nearly a year.

What happens to countries that borrowed heavily in dollars?

They get squeezed hardest. When the dollar strengthens, countries and companies with dollar debt need more of their own currency to make the same payment. Add in pricier energy imports, and countries like Egypt and Turkey face pressure from multiple directions: a weaker local currency, costlier imports, and more expensive debt, all at once.

Which countries benefit when the dollar and oil prices rise together?

Countries that export energy, earn revenue in dollars, carry manageable dollar debt, and have a currency that holds steady tend to come out ahead. The U.S., Canada, and Norway fit that mix well. Brazil benefits on exports but carries enough dollar debt that consumers still feel a squeeze. Russia gains from higher oil, but sanctions limit how much it can capture.

What Is the Dollar Smile — and Why It Matters

Get in Touch

Loading blog post...

What Is the Dollar Smile — and Why It Matters | Dunham