Bond investors have shifted to a defensive stance since the Middle East war injected fresh risk into markets, with many loading up on short-term U.S. Treasuries ahead of the Federal Reserve’s monetary policy decision. On Wednesday, the Federal Open Market Committee is widely expected to keep its benchmark overnight interest rate in the 3.50%-3.75% range at the end of a two-day meeting, as policymakers assess how the Iran war may influence their dual mandate of price stability and maximum...