https://www.theregister.co.uk/2018/06/21/supreme_court_ends_internets_escape_from_state_sales_tax/

Internet retailers will soon be required to pay state sales tax across the entire United States following a 5-4 decision by the Supreme Court.

The decision [PDF] will have a huge impact on American ecommerce, with large companies required to calculate, charge and hand over billions of dollars through dozens of different taxes.