The FX war recently launched by every central bank in the world, just entered its modern warfare stage: we have learned that the Mexican Central Bank has just sold $600 million worth of USD options. That's right - the central bank of our southern neighbor has moved beyond merely pedestrian cash interventions and has entered the derivatives game, in their attempt to raise the US peso and lower its Mexican equivalent. While there is no immediate indication of how the NAFTA treaty reacts to such outright open aggression between member states, it will likely be modestly to quite modestly frowned upon by the central banks of Canada, and most certainly, our own Fed. What we would love to find out, however, is who it was that was on the other side of the transaction, and bought $600 million worth of USD options. It would be supremely ironic if it it is discovered that it was the FRBNY that was taking the other side of the trade, as it would confirm that central banks have now gone AIG on betting on the outcome of currency wars.
Either way, the incremental systemic complexity introduced by this action will make plain vanilla interventions increasingly more unpredictable, and it is a likely validation that many other central banks also engage in this kind of synthetic trading. Also, who is to stop the counterparty on such trades to suddenly ramp up colletaral requests, very much in the fashion that Goldman and JPM destroyed AIG and Lehman, respectively? Should the Fed need to really pounce on the dollar, all it needs is to get the bank that did the deal (or itself) to make a few calls, and increase margin requirements from 5% to 100%+, forcing an immediate unwind of the transaction, and causing who knows how much havoc to both the synthetic and cash scenes.