Oh, I know, I just think there are some things they could deny without compromising future non-denials. Things like, what do you know about interstellar objects for instance. They could say, we don't. I suppose there is a non-zero chance that in the future there will be an interstellar object they have interest in, not far above zero.The CIA neither confirms nor denies absolutely everything. It's their job to neither confirm nor deny everything.