"...we can't compete with slave labor..."

Since all state and federal prisoners in the USA are legally slaves*, and jurisdictions demonstrably lease those slaves to corporations that use them to provide labor, and that imprisoned population is higher in the US than any other nation, I very much doubt we aren't outcompeting other slave labor markets. What we cannot do is enable lawful labor markets to compete with slave labor markets the USA itself leads.

"...it is impossible to compete with China on goods where it costs less to buy from China, than it costs to ship from America."

This is why bespoke local production, i.e. making the products ourselves, is how to outcompete Chiner, and every other centralized production facility.

"...all that extra money just gets paid to the banksters."

This is exactly the reason for all economic policy. The policy that best delivers wealth to the investors that own corporations is what the bribed and blackmailed lawmakers in every country make.

It is a mystery to me how China can ship to the US for less than US manufacturers can. Amazon seems to have become an empire and Jeff Bezos one of the richest men in the world by this mysterious means. However that is accomplished we mere mortals are prevented from using that mechanism in order to facilitate the growth of Chinese manufacturing and the destruction of American manufacturing. Trump seems to be unable to address that mechanism, proposing to overwhelm it using tariffs, simply adding tax cost to the price of Chinese products replacing the mysterious shipping subsidy. It seems more and more valuable to me to understand that mechanism in view of that further demonstration of it's inability to simply be eliminated or stopped, but can only be overcome with punitive taxation.

Thanks!

Edit: *the state of Oregon has amended it's constitution removing the exception to the ban on slavery it formerly contained, mirroring the exemption in the US Constitution to the ban on slavery for those convicted of crimes. At least prisoners of the state of Oregon are not today lawfully slaves, although I am unaware that has made any actual difference in treatment of those prisoners, or the leasing of their labor to corporations.