I was led to believe that the US does have internal sources of these, but they are largely undeveloped. For years the processing could not economically compete with China so shutdown.

Which is to say, given internal subsidies, the US could eventually produce some on its own.

Unless I misunderstood the situation.

I believe we both share this understanding, the problems are

1. China controls ~90% today

2. The US will find it difficult to build out because of how dirty and environmentally damaging mining and processing are.

I did see some research last week about a better way to process rare earths, but it is still research and will need to be industrialized.

Regardless, it will take many years (decade+?) to become self sufficient and China is already willing to and increasingly restricting them