That’s the title of Ian Talley’s piece in a recent Wall Street Journal online edition. The question arises from the People’s Republic of China’s open manipulation of its currency through its control of the yuan’s exchange rate in the currency markets. The PRC executes this manipulation by limiting the range of values within which the yuan is permitted to trade in those markets.

The question gains currency (sorry) as Congress contemplates adding an anti-currency manipulation clause to the Trans-Pacific Partnership free trade pact or to the fast track trade bull currently in progress of a sort. But that’s currency manipulation from the other side of the matter: instead of a country manipulating its own currency, this clause says the currency must be manipulated according to our imperatives:

Some US lawmakers are channeling their constituents’ long-held grievances by pressing to incorporate enforceable currency provisions….

The problem from this side of the coin (sorry, again) centers on the determination of what is a “fair” value for a nation’s currency, who gets to make that determination, and on what grounds. The point of Talley’s article concerns the difficulty of making those determinations.

It’s really quite simple, though. There are only two ways to determine the value of a currency. One is that a currency is worth what the nation’s government says it’s worth. (This, incidentally, blows up the gold bug argument that the US should go back to a gold standard for the dollar, that being the only way to bring stability to our currency. But the gold would have the value our government says it has, and nothing else, as FDR demonstrated when he devalued the dollar against gold in the ’30s.)

The other way, the free market (and so most moral) way, is this: let the currency float; its value is what the market says it is, empirically, by what the participants in that free market—free men and woman, acting voluntarily according to their own wants and needs—are willing to exchange currency for.