Economists say tariffs can increase prices for consumers, but Robert Lighthizer, President Trump's former trade chief, argues they're necessary.

By targeting allies and neighbours with tariffs, the US is playing into the hands of China. “Our strategy on tariffs will be to shoot first and ask questions later.” That was what one of Donald Trump’s key economic policymakers told me late last year.

Ending tariff exemptions on low-cost packages from China has broad bipartisan support in Washington, and Trump pulled the plug when he raised tariffs on Chinese goods by 10% earlier this week. Goods sent through duty-free packages became subject not only to existing tariffs — 25% for many Chinese products — but also the new 10%.