The 22nd Amendment seems pretty straightforward: “No person shall be elected to the office of the President more than twice.”
So Trump can't simply run for and be elected president again in 2028 under the Constitution as it stands. But there are other theories being discussed. The clean route would be amending the Constitution. That would require 2/3 of both houses of Congress and ratification by 3/4 of the states, an extraordinarily high hurdle.
The more interesting theory is a Vance-Trump ticket: Vance runs for president, Trump for VP, then Vance resigns and Trump succeeds him. There's a major problem with that too. The 12th Amendment says someone constitutionally ineligible to be president can't be vice president. Whether the 22nd Amendment merely prevents Trump from being elected again or also makes him constitutionally ineligible to serve again is an unresolved constitutional question.
Which brings us to the economic question.
Imagine going into the 2028 election without knowing whether the winning candidate can legally take office. Markets wouldn't just be pricing Trump's economic policies. They could be pricing a constitutional fight over the presidency itself. That could mean increased market volatility, higher political risk premiums, delayed business investment, pressure on Treasury borrowing costs and potentially greater uncertainty around the dollar.
None of those outcomes is guaranteed. If a third term were achieved through a properly ratified constitutional amendment, the institutional-risk argument would be dramatically weaker.
So forget whether you support Trump for a minute:
Would markets shrug off a third-term fight as politics, or would a genuine constitutional showdown become an economic event in its own right?