President Trump on Wednesday defended his desire to transition away from the social-distancing efforts that have closed down much of the U.S. economy.

“The more aggressively we commit to social distancing — so important, social distancing, such an important phrase — and we do it right now,” Trump said at the now-daily White House press briefing on the coronavirus pandemic, “the more lives we can save and the sooner we can eventually get people back to work, back to school and back to normal."

He looked up from his prepared remarks.

“And there are large sections of our country that probably can go back much sooner than other sections,” he added, “and we are obviously looking at that also. People are asking, is that an alternative? And I say, absolutely, it is an alternative.”

The idea that Trump has been moving toward all week is this: boost the economy by allowing states or regions with fewer confirmed cases of the coronavirus to resume normal or close-to-normal economic activity. Older Americans, he has said at other times, would still be distanced, given the increased mortality rate from covid-19, the disease the virus causes, among people over the age of 60. Everyone else, though? Maybe they can get back to life as normal.

Trump’s eagerness to have the economy motor on despite the coronavirus’s spread is not a new development. It is, if anything, the instinct that best defines his reaction to the global pandemic. By toying with the idea of opening states back up to normal interactions, though, he risks repeating the mistake he made a month ago: ignoring the threat of explosive growth by assuming that things will remain under control.

Since the beginning of February, the number of confirmed coronavirus cases in the United States has grown dramatically. Even three weeks ago, according to data from Johns Hopkins University, there were only about 200 cases in the country. Two weeks ago, there were 1,700 cases. A week ago, 14,000. Now? Nearly 70,000.

That sort of growth is better viewed on a logarithmic scale, as below. A line that heads up and to the right shows growth multiplying exponentially. That’s what the number of U.S. cases has done since late February.

(A jump in late February is a function of adding in passengers from a cruise ship on which the virus spread widely.)

Why this level of growth? Because it’s a highly contagious virus. Once the virus was known to be transmitting without containment — something that was publicly obvious on Feb. 26, with the first reports of community transmission in the United States — significant growth was inevitable. The country’s slow rollout of testing means that we learned about the community spread of the virus later than it began. Scientists tracking infections after the fact estimate that the virus was spreading in Washington state for weeks before it was detected.

Trump’s first briefing on the coronavirus was held at the White House the same day that the first case of community spread became publicly known. It was not addressed during the briefing. Instead, Trump said that there were 15 people with the virus (excluding those from the cruise ship) and that “within a couple of days [the number] is going to be down to close to zero.”

“That’s a pretty good job we’ve done,” he added.

That was Trump’s approach: The virus is not a big deal, and we have it under control. The economy was strong and would do fine. At a town hall that aired on Fox News on March 5, Trump even suggested that the virus might be a good thing for the economy, prompting people to stay in the United States instead of going overseas to spend money.

All of this is well-worn terrain by now. The number of cases soon exploded across the country. New York City has emerged as the epicenter of the outbreak in the United States, and hospitals in the city are increasingly strained in efforts to handle the influx of covid-19 patients.

Trump’s announcement on March 16 that he was advocating for increased social-distancing measures, including limiting gatherings of large groups and recommending against dining out, was an important step in limiting the spread of the virus and, therefore, reducing the strain on hospitals, health experts said. But Trump has grown exasperated with the effects on the economy. So he has transitioned: Maybe those less-affected regions could get back to work. Maybe we could just keep distancing measures in places such as New York and Washington and let places with fewer cases go back to normal.

Again, this is almost exactly what he was saying about the country in general a month ago. Maybe the virus is under control and will fade away, and we can go about our business as normal. He has narrowed the geography of that claim, but the argument is the same.

The new argument may actually be worse than the one he made at the end of February. The spread of the virus in all 50 states is now demonstrated — and in all 50 states, the rate of growth in the past few weeks has been exponential.

A few states have the most cases, notably New York, Washington and California. But even smaller states have seen rapid growth in the number of cases.

On March 17, Trump praised the state of West Virginia for “doing a good job” in keeping the virus out. At the time, it had no confirmed cases. A few hours later, though, it reported its first case. By the beginning of this week, it had more than 10. Now it has more than 50.

Even more rural states with fewer cases are sounding the alarm about the virus’s spread. A mayor in Kentucky warned his constituents that the virus was “a serious ordeal."

“In fact, it’s a big [freaking] deal,” he added in a Facebook post which used another word instead of “freaking.” “Stay at home.”

Lt. Gov. Will Ainsworth (R-Ala.) warned that the virus was growing exponentially in his state.

Anthony S. Fauci, a leading member of the White House’s coronavirus task force, told CNN’s Chris Cuomo on Wednesday night that, while measures might be able to be eased in some places, there weren’t always good data on where that might make sense.

“There are other parts of the country, which we need to get a better feel for what is going on,” Fauci said. “And the way we do that is by increasing testing and identifying people who are infected, isolating them, getting [them] out of circulation, and then do contact tracing.”

The existing data on confirmed cases, which depends on tests being conducted, shows that the virus is spreading faster in some places than others. In Nebraska, for example, the virus is spreading more slowly than in Michigan, where it is spreading relatively rapidly.

Even in Nebraska, where about 1,600 tests have been conducted, there are 74 confirmed cases — up from 29 a week ago.

Fauci is broadly recognized as the country’s leading authority on the pandemic and the government’s response. His limited endorsement on CNN of scaling back some distancing efforts is significant. But that endorsement did not include the sort of rapid turnaround that Trump has been talking about this week.

“You’ve got to understand that you don’t make the timeline. The virus makes the timeline,” Fauci said. “So, you’ve got to respond in what you see happen.”

“And if you keep seeing this acceleration,” he continued, “it doesn’t matter what you say, one week, two weeks, three weeks. You’ve got to go with what the situation on the ground is.”

Once again, this isn’t the message that Trump wants to hear.