President Trump’s fiscal year 2027 budget is built on a single, load-bearing bet: that the U.S. economy can grow at 3% annually for the next decade. The White House says that growth will flood federal coffers with new tax revenue and eventually bend the national debt, now sitting at over $39 trillion, onto a downward path. It is an optimistic vision. It is also, Federal Reserve Chair Jerome Powell suggested last month, the kind of optimism that has repeatedly failed to reckon with what he called an “unsustainable” fiscal trajectory that “will not end well.”
A leading budget economist explained to Fortune why the sustainability picture isn’t getting better, even if you accept the White House’s growth numbers at face value.
