The US ban on supersonic overflight killed supersonic travel, and therefore Concorde. 1960s tech was only able to build planes that could go about 3500 nm, and

The US ban on supersonic overflight killed supersonic travel, and therefore Concorde. 1960s tech was only able to build planes that could go about 3500 nm, and a huge proportion of flights in that range at that time was transcontinental flights across North America. The cancellation of all American operator orders made the project impossible to break even. The fuel costs were nasty, but not the end of the world. The existence of first class travel shows that there’s a market for expensive, inefficient long haul flights. If supersonic passenger flight had been able to survive American protectionism, it would have avoided missing out on the last 50 years of R&D, so SSTs today would have gotten much more efficient, just like today’s sub sonic jets have become.