The USA is objectively corrupt from the top, have recently removed themselves from non nuclear proliferation and climate treaties .. as a country the message seems clear that USA don't care two shits about the rest of the World.
The idea Trump would open his response to an epidemic up to international inspection is just laughable - and I say his, rather than USA government's because that's how things appear to work there.
Trump has not even nearly as much power as you seem to think. We hear about his abuses of power because hearing ”California government implements reforms to reduce carbon emissions, in spite of Trump” doesn’t generate as much emotions as his corrupt practices.
Imagine a Chinese provincial government openly (key word openly) going against the CCP’s wishes. Or a judge, or a prosecutor.