US stock futures wavered after investor optimism largely persisted for another day despite growing warnings that relief over trade developments could be short-lived. Futures attached to the Dow Jones Industrial Average (YM=F) rose 0.1%. Futures attached to the benchmark S&P 500 (ES=F) and the tech-heavy Nasdaq 100 (NQ=F) traded flat. On Monday, stocks ticked up despite the US losing its last AAA credit rating on Friday. Since the US and China struck a deal to temporarily roll back tariffs last week, Wall Street has been shaking off fears of a...