Should the government be able to keep secrets?

I think there is a limit to what the government should be able to keep from us. We have right to know whats going on in our country but at the same time I can see how keeping some things secret for the safety of the people. Im sure there are many strange and interesting things in the world that average people know nothing about because the government keeps it top secret. Things like the magic johnson case, where now he suddenly doesnt have aids. People believe the government has found a cure for aids but is keeping it top secret.