Intelligence officials were, behind the scenes, questioning whether the benefits of gathering counter-terrorism information justified the colossal costs involved. Then Snowden went public and essentially forced the agency's hand.,
So they could have said, "OK, you know what, you're right. The benefits of this program are outweighed by its costs, the American people have a right to be involved in the decision about surveillance, and we are going to shut the program down." They would have been the bigger men, demonstrating that standing united is more important than ego.
But instead, they cried, "NO! If it's your idea, if you're trying to force us to stop, well then FUCK YOU! We'll do what we want, whether you like it or not! YOU CAN'T TELL US WHAT TO DO!" Like a petulant child throwing a temper tantrum. Can't back down from a fight, that might make them look like they don't have a giant chip on their shoulders.