A secret meeting at the White House

I just finished reading the article "Obama visits Bush at White House for private chat" by David Lightman at MccLatchy Newspapers. Many details were kept secret but they apparently talked about eonomic and national security issues. The two men talked for an hour and five minutes, while Laura Bush gave Michelle Obama a tour of the private residence of the White House. I think that the importance of this is that our president now and our future president, are discussing ways of fixing our countries current situation. What I don't understand is why they didn't say what they talked about. I think that their business is ours, right? Why didn't they tell us? Are they allowed to keep secrets from american citizens? What I also thought was weird was that the White House secretary and the Obama spokesperson didn't say anything about their meeting. Did Obama and Bush not discuss anything important? Or what? I just thought it was interesting that citizens of this country, aren't allowed to know what is going on at the White House.