Trump is now tying trade with major partners to the Fed's interest rate decision, a threat that would hurt the U.S. economy most if he followed through.

• After a strong August jobs report, Trump demanded lower rates and said he would halt trade with countries the U.S. runs deficits against — Canada, China, the EU, Mexico and others — if the Fed refuses.
• Those countries have no say over U.S. interest rates, so the threat is aimed at the Fed but the damage would land on trade partners and on America itself.
• Fed chair Kevin Warsh is leaning the other way, hinting at raising rates to push inflation down, setting up a direct clash with the White House.
• Canada's rates are lower because its economy is weak and its mortgages reset every few years; the U.S. is still fighting inflation, which is why its rates are higher.
• Cutting rates now could push inflation back up and make everyday costs — including high gas prices — worse, not better.

Outlook: Expect an escalating fight between Trump and the Fed, with markets watching whether the threat turns into actual trade action.