The yield on the 10-year U.S. Treasury bond has risen to 4.43%, close to the psychological barrier of 4.5%, the highest level since June. The Federal Reserve has recently cut interest rates to cope with the economic slowdown, but too much interest rate cuts may bring inflation risks. Once the yield exceeds 4.5%, it may trigger two situations: one is that the Federal Reserve raises interest rates to control economic overheating; the other is that the confidence in U.S. bonds is lost, leading to a large-scale sell-off, pushing the yield further up. Trump's tax cuts and loose policies have pushed down interest rates, and their impact has not disappeared yet. If the yield exceeds 4.5%, it may trigger the Federal Reserve to raise interest rates or sell off U.S. bonds, causing market volatility.