Directional moves in the Chinese stock market may act as the "canary in the coal mine,"  for our stock market. Its direction may precede changes in trend in our market. John Reizner addresses in this post whether or not financial market conditions are simliar in form today to those right before the crash. He cites part of his prescient 2007 article written before the financial crisis where he noted an unsupported speculation in the stock market.