Hedge fund trader James Litinsky turned a $20 million distressed bonds bet into a billion-dollar mining fortune—with a little help from Uncle Sam and the Chinese.

President Donald Trump’s “reciprocal” tariffs aim to level the playing field in global trade by imposing duties based on where a product is made.

Many smaller countries’ exports have faced 10 percent tariffs since the president first announced, then suspended, an initial wave of policies in April. Others have staved off eye-watering rates after brokering deals with the United States that set their tariffs generally between 15 and 20 percent.