President Trump’s latest moves included a 104 percent tariff on Chinese goods. Stocks and bonds slumped as Beijing hit back with its own levies and European leaders prepared retaliation measures.

Neither side wants to look weak by backing down on tariffs. But if their trade relationship collapses, the global consequences could be profound.

The U.S. has sent more forces to Syria, tamping down on the immediate threat, but experts warn that the extremist group could break thousands of hardened fighters out of prison.

The European Union is poised to approve a plan to hit back at President Trump’s steel and aluminum levies. Further measures could come next.

The new levies come as nations on the continent continue to struggle with the fallout of the Trump administration’s dismantling of the U.S. Agency for International Development.

As its trade negotiators headed to Washington for talks, South Korea announced measures to support the country’s carmakers who were badly hit by the levies announced by President Trump.

Europe wants to negotiate, but it is also trying to project strength. As Trump warns nations against retaliation, that strategy could be perilous.

Expected talks between Iran and the United States would be a late, and perhaps last, opportunity to control Tehran’s nuclear ambitions and avoid war.

On the war, President Trump is more aligned than his predecessor with the aims of Prime Minister Benjamin Netanyahu of Israel and his right-wing coalition.

Ms. Truss, Britain’s prime minister for 44 days, was forced out after her radical policies caused a market meltdown. But there are some key differences with President Trump.