The U.S. trade deficit has gone from about -150 G$ in 1998 to about -525 G$ today, which is, like, a LOT...
...unless you include the environmental costs of the trade, in which case the U.S. basically is able to avoid the implicit costs of CO2 emissions by exporting a significant chunk of them to China. That decreases the value of the U.S.-China trade deficit, and depending on how you price the CO2 emissions, can even wipe it out completely.
(And lest you think I know something about economics, the only reason this makes any sense to me is because the talk just finished, and it's still fresh in my brain.)
