Up until March 16, the president had minimized the crisis.
News organizations like The Washington Post have tracked what the president has said, over time, about the coronavirus crisis. See a previous blog post with a link there to those historical remarks, A Timeline of President Trump's Remarks about the Coronavirus.
I don't know what happened on March 16. Maybe he got out of the other side of the bed? More likely, a political adviser got his attention, by "slapping him upside the head with a 2X4" and saying, "Pay attention. You, your presidency, your re-election is at stake here in this moment in time." Someone had to make it very personal to him, because he only cares about himself.
Then on March 16, "This is a crisis of major proportions, we are doing everything possible and in our power to respond." And, he is sure to have added, "By my quick action to impose the travel ban from China, we made it much better for us."
So the worm has turned. I'll be doing another blog post on the fact that this event when the after action reports are written should be titled, "Too Little, Too Late." National leadership has been reactionary and not proactive. True leadership transferred to the governors who have led as best they can with the authorities they have.
I have to note that as of this morning, Mexico only has 100 cases of coronavirus identified. Maybe they are even further behind the USA in testing, but I doubt it. I thought all those Mexicans trying to enter the United States were "carrying diseases" as the president has stated before. Today, Mexico is a better place to be to avoid COVID-19.