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Good morning.

Here’s what you need to know:

The real threat to the economy

• Under the steep tariffs on steel and aluminum that the U.S. has imposed on its closest allies, prices are likely to rise and supply chains will probably be disrupted.

But our senior economics correspondent says there’s a longer-term danger to the American economy: “The administration’s trade policy is displaying an erratic, improvised, us-against-the-world quality that is anathema to businesses that must make long-term decisions about how to deploy capital.” Read more here.

Canada, the European Union and Mexico will face 25 percent tariffs on steel and 10 percent on aluminum. They quickly denounced the tariffs on Thursday and prepared to retaliate.

• In moving forward with tariffs on national security grounds, the Trump administration now faces a test of whether its aggressive strategy can extract promises from trading partners.