It looks like slow ramp up of testing, combined with a few weeks of rampant spread without social distancing, was enough to get the spread to an exponential phase.
What Italy, Spain, and now many states in the US are doing will have effects. But first we'll see an uptick in cases and fatalities, as testing increases, and the disease's extraordinarily long incubation time runs through it's course in those already infected.
To the best of my understanding, we can expect April and early May to be pretty bad, before things settle down.
But it we relax social distancing and isolation once things do settle, we risk a resurgence.
On the other hand, it's not like social distancing is without a cost.
I had a mild cough last week so I stayed at home for the last 3 days of the week out of an abundance of caution. By Monday, we'd all been asked to work from home indefinitely. It's starting to get to me, that's for sure. And this is just the second week.