US stocks tumbled as President Donald Trump continued to lash out at Powell on Monday, calling on the Federal Reserve chairperson to cut interest rates as signs mounted that Trump's trade war was pushing the US economy into recession. The dollar fell along with long-term US Treasuries. Trump said on his social media site that he favored "pre-emptive rate cuts" and willfully called the Federal Reserve chairperson a "loser". Since last week, Trump has "shelled" Powell in succession, raising the question of whether the Fed can maintain its independence and be free from political influence. This is about people's confidence in the US financial marekt. "The market doesn't want the independence of the Fed challenged," said Joe Saluzzi, co-manager of institutional trading. "The market can at least try to predict what an independent Fed would do. If the Fed's independence is challenged, there could be more volatile [unpredictable] decisions. The market doesn't like unpredictability."