A federal appeals court has ordered a halt to above-ground construction on the White House ballroom project, ruling that the work cannot proceed without congressional sign-off. The decision is a win for historic preservation advocates, who argued that unilateral changes to the executive mansion's exterior sidestep the checks that Congress is meant to provide over alterations to a building that belongs to the public, not any single administration. The ruling underscores that even presidential pet projects are not exempt from oversight when they touch a structure steeped in national history. Preservationists have long warned that allowing construction to move forward without legislative approval would set a troubling precedent, letting future occupants of the White House reshape a shared national landmark on their own authority. For now, the court's decision pauses the building work and sends the matter back toward Congress, reaffirming that decisions about the White House's physical legacy require more than one branch's blessing.