New cases by continent:

This, and the geographic pattern of infection, suggests a very specific pattern:
- The first wave was triggered by travel from Europe, mostly via New York City. The U.S. was able to begin fending off that wave, but it was complicated by Latin America (with which it shares a land border) seeing a much bigger wave that has begun to overwhelm the American efforts so far—an issue that Europe has not yet had to face and may never have to face.
You may recall in 2009 that swine flu entered our country from Mexico. The wave attacking the south and west is likely coming from the same place.
So blame "lack of social distancing" all you want. Until the rest of the continent gets their infections in check, there is no hope we will ever do the same.