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China and South Korea have flattened their curves. Italy, Spain, Germany and the Netherlands have begun to flatten their curves.

The United States still has not.

More than half of all confirmed coronavirus cases in the United States have been diagnosed in the past five days. Depending on what data source you use, yesterday was either the worst day for new cases or one of the worst. And more than 3,000 Americans with the virus have died, meaning the death toll has now exceeded that of the 9/11 terrorist attacks.

As you can see in the chart above, the other three countries with the world’s largest number of confirmed cases — Italy, China and Spain — were all making significant progress at a similar point in their outbreaks. But the response in the United States has been slow and uneven.