When the number of active cases drops to zero, when basically everyone is tested and contact tracing has resolved all current active cases, when a large fraction of the population (25%-75%) already has had it, or when a vaccine or extremely good antiviral is developed and massively deployed.

I can't see any of these happening for months. To do any of them requires massive mobilization that isn't happening in the US.

Eventually COVID-19 will probably just be endemic like the seasonal flu. Hopefully it's also mutated by that point to be much less dangerous.