Well yeah, but that was an exception. It was in danger of being activated, and was overrun with flood. But now that the Ark is gone, they're just a bunch of floating space rings, and the UNSC's primary goal is to find them and establish research bases on them. Not destroy them.
I like nonsense, it wakes up the brain cells. Fantasy is a necessary ingredient in living, it's a way of looking at life through the wrong end of a telescope. Which is what I do, and that enables you to laugh at life's realities. — Dr. Seuss