President Trump on Tuesday levied new tariffs on goods imported from Mexico, Canada and China, the three largest trading partners of the United States, following executive orders he signed last month targeting the countries, a move that risks unleashing a damaging trade war.

Trade wars were a feature of Mr. Trump’s first term in the White House, too. But his latest tariffs on Canada, Mexico and China, which took effect at 12:01 a.m. Eastern time on Tuesday, may broaden the scale of disruptions. The three countries account for more than a third of the products brought into the United States, supporting tens of millions of American jobs.

How sweeping are the tariffs?

All goods imported from Canada and Mexico are now subject to a 25 percent tariff, except Canadian energy products, which face a 10 percent tariff, according to the executive orders. Those levies were initially set to take effect last month, but Mr. Trump agreed to pause them for 30 days after the Canadian and Mexican governments promised to step up their oversight of fentanyl and the border. Products coming from China are subject to a 20 percent tax, double the 10 percent Mr. Trump imposed last month.

The auto and electric equipment sectors in Mexico are most exposed to disruption from sweeping tariffs, as is mineral processing in Canada, according to economists at S&P Global. In the United States, the largest risks are to farming, fishing, metal and auto production.

What should consumers expect?

Some companies may try to pass the cost on to their customers by raising prices. Others may choose to eat the cost of the tariff. Companies may also try to force foreign suppliers to bear the burden by negotiating lower prices for their products.