It isn't now. Tariffs (long-standing ones that have survived both parties in power) in fact are keeping byd from the US market to protect primarily Tesla.

In Tesla because of the brilliant behavior of its precious CEO, will likely be specifically targeted for exclusion from subsidies in the EU, and inevitably at home when this administration passes by

Or any of hundreds of other national space programs and companies, in countries which would have been ecstatic to pay 10X the US Govt's "subsidies to SpaceX", to put themselves or their nation's company into SpaceX's current position of utter global dominance.