President Donald Trump wants to use funding for military projects across the country to pay for a wall along the U.S.-Mexico border. He’s thinking about taking $3.6 billion from the Department of Defense. But the man temporarily in charge of the Defense Department is not sure he should do that. Acting Secretary of Defense Patrick Shanahan said he has made no decisions on whether the southern border wall is militarily necessary. The appropriations bill says that is a crucial determination before military construction funds could be redirected to build it.

Prior to Feb. 15, the administration had not decided which military construction projects are slated to be stripped of their funding. Congress had set aside about $10 billion for base projects, and $3.6 billion of that could go to the border. Feb. 15, Trump declared a national emergency, which gives him the authority to access unspent funds in defense accounts. Congress and at least 16 states disagree with the president and are suing to stop the funding transfers.

Shanahan is expected ultimately to support the wall construction, but he is still determining how military spending could support it. “We understand there are some priorities that won’t be considered,” Shanahan said. “Military housing … I’ve received a number of letters, I’ve had lots of feedback saying, ‘Do not jeopardize the projects that are underway,’”

Shanahan added, “I appreciate we’re trying to work through this very complicated situation … that people remind us, these are real, live, very important projects.”

In a recent presentation, Fort Bragg, North Carolina, officials outlined $699 million of planned construction projects over the next six years in addition to the $343 million the Department of Defense has underway at the local post. That’s more funding than is assigned to all the military bases in Florida, which could lose up to $177 million for planned construction, according to a list of eligible projects compiled by the House Appropriations Committee.

Some projects planned at Fort Bragg could be vulnerable because they don’t contribute to military readiness. The multimillion-dollar Freedom Crossing entertainment and retail district for active-duty and retired service members and their families has a $27 million budget, according to the Army & Air Force Exchange Service. It will include three retail buildings, a 42,000-squarefoot movie theater and an outdoor public entertainment and event plaza.

The bulk of other construction projects will be for the benefit of the installation’s special operations mission. The recent disclosure from Fort Bragg officials also earmarked $788 million in what they called a wish list for a fire station, Pope Army Airfield upgrades, tactical equipment maintenance facilities, barracks and training areas.

Fort Bragg is the world’s largest military installation by population and is expected to continue growing in the coming years. In addition to being home to the Army’s airborne and special operations units, the post is also Forces Command Headquarters and is home to the Army Reserve Command. It is colloquially referred to as Pentagon South.