First Brexit step.
Forget US as no longer a friendly power (note tariff justification).
Do deal with Commonwealth countries. A free trade block which includes India, Canada, the UK, Australia, NZ, Singapore and in sum 53 Commonwealth countries would provide a new actor on the world's economic stage. Add in the EU and Japan for broader deals and you have an economy which dwarfs the US and China.
If so, who cares that the US is isolating itself.