Donald Trump has argued for quite a while that he expects Congress to approve $5 billion in taxpayer-funded spending for his proposed border wall. If lawmakers balk, the president has said he’s prepared to shut down the government.

This morning, White House Press Secretary Sarah Huckabee Sanders suggested Trump will not follow through on those threats. The Washington Post reported:

…Sanders told Fox News Channel: “We have other ways that we can get to that $5 billion.” “At the end of the day we don’t want to shut down the government, we want to shut down the border,” Sanders said. Sanders said the White House was exploring other funding sources and believed it could be legally done.

To the extent that people were concerned about a shutdown in three days, Sanders’ rhetoric, if it’s to be believed, is reassuring. The sooner the White House backs off its demands for $5 billion for a border wall, the sooner Congress can keep the government’s lights on and start preparing to leave town for the holidays.

But when Trump’s chief spokesperson hints at “other ways” to get the money, it’s important to ask for details about the alternate revenue streams.

In fact, in context, the Fox News host specifically asked this morning, “In a legal sense, you could use defense money for border security?” Sanders replied, “There are certainly a number of different funding sources that we’ve identified that we can use, that we can couple with the money that would be given through congressional appropriations that would help us get to that $5 billion that the president needs in order to protect our border.”

Putting aside the fact that Trump does not, in reality, “need” that money to protect the border – in fact, the president already declared the border “secure” just last week – the Fox News host followed up by asking about the legality of using military funding this way. Sanders said it’s “absolutely” legal.

The truth is a little more complicated.

If the White House is talking about using military resources for “border security” – deploying troops to the border, for example – that’s legal. It may be a pointless public-relations stunt, but it’s legal.

If, however, the Trump World is talking about redirecting funds from the Pentagon budget to finance border wall construction, that’s a very different story. As we discussed in March, when the president said the Defense Department is so “rich,” he could divert funds from the Pentagon to fulfill his dream, he doesn’t have the legal authority to take federal funding devoted to one purpose and then redirect it to some other purpose.

The Washington Post reported at the time:

[T]he military is not likely to fund the wall, according to White House and Defense Department officials. The Pentagon has plenty of money, but reprogramming it for a wall would require votes in Congress that the president does not seem to have. Taking money from the 2018 budget for the wall would require an act of Congress, a senior Pentagon official said. To find the money in the 2019 defense budget, Trump would have to submit a budget amendment that would require 60 votes in the Senate, the official said.

Leading congressional Democrats have already told the administration that rerouting federal funding this way would be illegal. Vox even tried to give the president a hand by putting together a handy explanation of the appropriations process.

If Team Trump is backing away from the shutdown ledge, that’s good news. If Team Trump is planning to pick a prolonged legal fight over misusing funds from the Pentagon budget, that’s not at all good news.