By Pete Schroeder WASHINGTON (Reuters) – Rising geopolitical tensions and a looming Federal Reserve move to tighten monetary policy weighed down Wall Street on Tuesday and helped to drive oil higher. After shaking off steep midday losses to end in positive territory on Monday, all three major U.S. indices were lower Tuesday, seemingly on pace to continue a three-week slide that was capped by last week, the heaviest losses in markets since 2020. The tech-heavy Nasdaq Composite posted the steepest losses in midday trading, down 2.94%, while the Dow Jones Industrial Average dropped 1.28% and the …