Military Language Difference
If you tell the Navy to secure a building, they will turn out the lights and lock the door.
If you tell the Army to secure a building, they will turn out the lights, lock the door and post an MP at the entrance.
If you tell the Marines to secure a building, they will assault the building, kill or capture everyone inside, fortify the building and turn it into an HQ.
If you tell the Air Force to secure a building, they will take out a three year lease with an option to buy.
Tell the Seabees to secure a building and they'll move it to a more protected location 600 yards off the beach. In about four hours.