“The case first reached the Court in late July 2019, after a lower federal court blocked the Trump administration’s attempt to transfer $2.5 billion that Congress appropriated for military pay, training, and similar personnel-related matters to wall construction. The administration claims it was allowed to do under a statute permitting the Secretary of Defense to transfer military funds “for higher priority items, based on unforeseen military requirements.”
But, as several lower court judges have pointed out, there’s nothing “unforeseen” about the circumstances that led Trump to build this wall. Trump’s campaigned on plans to build a border wall since 2015. In late 2018 and early 2019, Trump even shut down much of the federal government due to a disagreement over how much money should be appropriated to pay for the wall.
So Congress did not deny Trump much of the funding he sought because it failed to foresee an emergent problem that could only be solved by a border wall. It was well aware of Trump’s case for additional funding for his wall, and it rejected that case.”