Key Takeaways The S&P 500 is off to its worst start for a presidential term since 2009, when Barack Obama entered the White House in the midst of the global financial crisis.Traditionally defensive sectors have outperformed since Trump's inauguration amid growing concern that tariffs could usher in a period of stagflation.

Below are some of the sizable financial market moves prompted by the actions of U.S. President Donald Trump in recent weeks from his re-ignition of a global trade war to the signal that Europe can no longer take the support of U.