So political and economic observers might be wise to familiarize themselves with the wonky concept of "impoundment," which concerns what happens when congressionally appropriated money simply isn't spent by the president's executive branch.
This bit of Washingtonese is important, as it could be determinative about whether Musk and Vivek Ramaswamy and their new extra-governmental Department of Government Efficiency can follow through on some of their bigger ideas, such as cutting the annual federal budget by at least $2 trillion.
Musk and Ramaswamy are looking to cut a lot but lack any formal authority to do so; it's Congress that has the "power of the purse" to decide how governmental money is used.
But the incoming Trump team may aim to at least tweak that.
Just this week, in a Wall Street Journal op-ed focused on a range of strategies the two men are looking to employ, Musk and Ramaswamy noted the importance of impoundment to their plans and said the question may end up before the Supreme Court.
They argued that the current presidential limits are unconstitutional, saying Trump will challenge them "and we believe the current Supreme Court would likely side with him on this question."
Trump has also weighed in on the issue in a campaign video in the summer of 2023, when he said that the law "wrongfully curtailed" the president's powers in this area and called it "a blatant violation of the separation of powers."
A Watergate-era reform following abuses by Richard Nixon
Whether justices indeed agree with Trump and Musk remains to be seen.
But what will be at issue if a case reaches their docket is a Watergate-era reform called the Impoundment Control Act of 1974.
The law laid out a process that the president must follow if he or she wishes to diverge from congressionally mandated funding for any program.
In short: The White House needs to go back to Congress to ask permission.
Impoundment was indeed a power that presidents enjoyed for most of US history, but it was traditionally used only to send back excess funds if Congress put aside too much.
That changed when then-President Richard Nixon attempted to stymie an environmental project using the impoundment process after Congress overrode his veto and allocated the money against his wishes.
That action led to the 1974 law (part of a wave of post-Watergate reforms) and was further solidified by a Supreme Court ruling in 1975 that has been interpreted as saying the president can't use impoundment to frustrate the will of Congress.