The record volatility, and 400 point up and down days in the DJIA of last summer seem like a lifetime ago, having been replaced by a smooth, unperturbed, 45 degree-inclined see of stock market appreciation, rising purely on the $2 trillion or so in liquidity pumped into global markets by the central printers, ever since Italy threatened to blow up the Ponzi last fall. In short - we have once again hit peak complacency. Yet with crude now matching every liquidity injection tick for tick (and then some: Crude's WTI return is now higher than that of stocks), there is absolutely no more space for the world central banks to inject any more stock appreciation without blowing up Obama's reelection chances (and you can be sure they know it). Suddenly the market finds itself without an explicit backstop. So what are some of the "realizations" that can pop the complacency bubble leading to a stock market plunge, and filling the liquidity-filled gap? Here are, courtesy of David Rosenberg, six distinct hurdles that loom ever closer on the horizon, and having been ignored for too long, courtesy of Bernanke et cie, will almost certainly become the market's preoccupation all too soon.