US Defense Secretary Pete Hegseth told a federal judge that President Donald Trump’s proposed triumphal arch is a “generational national defense opportunity” in a legal briefing arguing the project is vital to protecting the nation’s capital.

Originally proposed as a monument to celebrate the country’s 250th birthday, Trump last month debuted a new justification for building it, saying it would double as a tourist attraction and military complex where drones and ammunition could be stored and military snipers could be posted.

The surprise proposal for this additional use of the 250-foot arch came as the project – a personal endeavor of the president that has become a key part of his legacy – faces a slew of criticism and two lawsuits aimed at stopping its construction.

In a written declaration submitted Wednesday, Hegseth defended Trump’s new rationale for the planned structure at Memorial Circle, a busy traffic circle between the Lincoln Memorial and Arlington National Cemetery.

The location overlooks major national sites that are frequented by federal officials and its height will create elevation advantage and line-of-sight connectivity, while its central location will improve the ability to identify and assess potential threats, Hegseth argued.

“It will be utilized as a dual-purpose structure: a major national monument that also incorporates military utility to support Homeland defense,” he said. “The elevated position can also support authorized protective-overwatch and counter-sniper personnel by improving observational, situational awareness and coordination with other security elements.”

In addition to Hegseth, Secretary of Homeland Security, Markwayne Mullin, also defended the need for the arch’s dual purpose, saying the location “provides opportunities for increased capability for information -sharing and logistical coordination.”The full-throated endorsements for the arch’s potential national security uses from two cabinet members comes as the project is facing key tests to its progress.

Hegseth’s and Mullin’s statements were part of the government’s submissions in a lawsuit being heard in the US District Court for the District of Columbia aimed at stopping the arch’s construction.

On Friday, the court will hold its next hearing on the case, which was brought by veterans who argued the arch dishonors the memory of the fallen at Arlington National Cemetery by blocking key sight-lines and overlooking the burial grounds.

And next Thursday, the arch will be reviewed by the National Capital Planning Commission (NCPC), the last of two federal agencies overseeing architectural and design changes in Washington, D.C. that must approve the project.

If approved by NCPC, the administration has already said they will start construction as early as that same day.

However, final plans for the arch submitted to the NCPC for its November 5th meeting that were released last week included no mention of the military component.

The plans excluded features such as the drones and snipers that Trump described in September, and the contours of the arch in the plans did not appear to reflect a national security purpose. Instead, they describe the project as a “ceremonial gateway” to the nation’s capital.

Hegseth’s Wednesday filing stated that the military components would not require any structural modifications or alterations. “The security features will be fully integrated into the existing design,” he wrote.

Trump has also claimed the need for national security enhancements as a justification for his project to build a White House ballroom where the East Wing once stood.