In the world where China wants to keep its own currency at a low value in order to continue the export-driven economic policy. Look, obviously China can sell i

In the world where China wants to keep its own currency at a low value in order to continue the export-driven economic policy. Look, obviously China can sell its US treasuries in exchange for "cash" (electronic balances in a current account). If it did that, the US would only benefit. If China then exchanged this USD "cash" into another currency, the worst that would happen is for the USD to reduce in value in the foreign exchange markets, which would boost US exports and therefore boost the US economy. Yeah, US consumers would have somewhat less purchasing power for some time, but that only balances out the fact that US consumers currently have somewhat more purchasing power than they would "naturally" have.