Yesterday afternoon, following the rout in the US stock market, we made a spurious preview of the true main event: "So selloff in JGBs tonight?" We had no idea how right we would be because the second Japan opened, its bond futures market was halted on a circuit breaker as the 10 Year bond plunged to their lowest level since early 2012, hitting 1% and leading to massive Mark to Market losses for Japanese banks, as we also warned would happen. That was just the beginning, and suddenly the realization crept in that the plunging yen at this point is not only negative for banks, but for the entire stock market, leading to what until that point was a solid up session for the Nikkei to the first rumblings of a ris-off. Shortly thereafter we got the distraction of the Chinese Mfg PMI which dropped into contraction territory for the first time since late 2012, and which set the mood decidedly risk-offish, although the real catalyst may have been a report on copper from Goldman's Roger Yan (which we will cover in depth shortly) and whose implications may be stunning and devastating and may have just popped the Chinese credit bubble (oh, btw, short copper). And then all hell broke loose, with the Nikkei first rising solidly and then something snapping loud and clear, and sending the index crashing a massive 1,143 an intraday swing of 9% high to low, leading to an over 200 pips move lower in the USDJPY, and leading to a global risk off across the world.