Yesterday, the United States surpassed China, becoming the world leader in COVID-19 infections. It's not hard to understand why. Social distancing remains very uneven. Domestic travel continues unchecked. Asymptomatic carriers stay on the move. Starting on the coasts, COVID-19 is now moving inexorably across the nation, coming to a city or town near you.
If you want to get a glimpse of how COVID-19 can spread, watch this clip from Tectonix GEO. It uses data from anonymized mobile devices to trace the movement of Spring Break partiers who congregated at one single Ft. Lauderdale beach, then moved back across the United States, in each case potentially bringing the virus with them. It's a quick case study showing how an infectious disease can spread through a country that wants to remain mobile come hell, pandemic, or high water.