Let's be clear: Nothing changed. The red curve is the sum of the blue curve and the green curve, one of which started out large and decreasing, while the other started out small and increasing. The initially-small curve was negligible until all of a sudden it wasn't.
This is relevant to the coronavirus situation. We don't have one big outbreak. Instead we have hundreds of smaller outbreaks, some of which are large but more-or-less under control, and some of which are small (for now) but out of control.
For this reason, it is arrant madness to try to predict what happens next based on the shape of the overall curve, on a nationwide, statewide, or even countywide basis. To properly model what's going on, you would have to use a super-fine-grained detailed model.
And that's not worth the trouble, because all the honest models — including the simplest ones as well as the fanciest ones — are telling us the same thing. And that agrees with what we already know, based on recent history in countries that have been successful.
We need high-quality readily-available PPE. We need comprehensive, reliable, timely testing. We need contact-tracing and lots of it. We need facilities for isolating people who might be contagious, so we don't have to isolate everybody else. The idea is to pounce on each little micro-outbreak *before* it gets big enough to show up in any statistical summary. Every country that has been successful has done it this way.
All this has been obvious since February. It's now June. The fact that these measures are not already in place is beyond scandalous, beyond outrageous, beyond criminal.