The fight over President Donald Trump's proposed triumphal arch has moved into federal court. The five-member Arlington County Board filed a lawsuit Thursday in the Eastern District of Virginia challenging the project's review process. The board, represented by the advocacy group Democracy Forward alongside the county attorney's office, describes the 250-foot-tall arch and its adjoining military observation deck as a vanity project that would be massively intrusive and harmful to the surrounding neighborhoods and sightlines. The suit asks the court to block any demolition or construction until a full environmental review is completed. The arch has faced a drumbeat of opposition. Veterans' groups have sought court orders to block it, architects have weighed in through their professional institute, and an advisory council tied to the project resigned — each challenge chipping at the administration's fast-tracked timetable. Timing is tight. Democracy Forward points to November 5 as the date of the National Capital Planning Commission's next meeting, when the committee could effectively green-light the start of construction. In early September, Interior Secretary Doug Burgum announced that excavation work for what he called the Great Triumphal Arch was about to begin. The lawsuit is the latest in a string of legal and institutional challenges to the monument, which has drawn opposition from veterans' groups, architects and local officials since it was proposed. Whether the courts intervene before the November planning meeting will determine if the arch moves from rendering to reality — or joins the list of contested monuments stalled by the very review processes meant to govern them.