U.S. stocks looked set to drop on Tuesday after President Donald Trump said he had removed Lisa Cook from her job as a Federal Reserve governor, reigniting concerns about the central bank’s independence under the current administration. S&P 500 futures slid 0.1%, and contracts tied to the tech-heavy Nasdaq fell less than 0.1%. The three blue-chip indexes finished in the red on Monday, as the rally sparked by Fed Chair Jerome Powell’s Jackson Hole speech faded.