Thursday morning's session opened with a 15-minute trading halt after a 7% slide in the S&P 500 index triggered the Level 1 marketwide circuit breaker. This is the second such marketwide trading halt this week (read: "How Trading Halts Impact ETFs"). Additionally, trading in Dow and S&P 500 futures was briefly halted overnight, after they hit their 5% "limit down" threshold. Among retail and professional investors, the trading halts have done little to soothe rattled nerves. Some market commentators have even begun to propose more extreme measures to protect the stock market, such as an immediate Fed rate cut to ... (full story)