Most American burgers are, in fact, not entirely American.

The patties grilled at backyard barbecues or flipped in fast-food restaurants are often a blend of ground beef, both homegrown and imported from other countries, especially Brazil. In school cafeterias and home kitchens, this global mix of beef is seared, fried and sizzled into millions of tacos, meatballs and lasagnas every day.

Now, President Trump’s dismantling of the global trading system through his imposition of broad-based tariffs is leading to shifts in commerce that could make winners out of countries like Brazil that produce commodities the world covets.

When it comes to beef — crucial to satisfying Americans’ hunger for cheap cuts of meat — tariffs will make Brazilian beef more expensive.

But at the same time, Brazil is suddenly a more appealing source for China, another enormous consumer of beef, because its trade war with the United States — and the high tariffs the two nations have imposed on each other — has left China looking for other countries with ample supplies of inexpensive meat.

While U.S. meatpackers, most likely anticipating escalating prices, have been stocking up on Brazilian beef in recent weeks, according to trade data, Brazilian beef exports to China also increased in April.

A farm near União Bandeirantes, Brazil.Credit…Victor Moriyama for The New York Times