I'd say that the answer mostly depends on what we are talking about to begin with...
Ergo: if its food, or something we put in our bodies ( including medicines, herbs, spices, and the like).. we have a right to know everything about it. Whether or not it is a Genetically modified Organism ( GMO) or not... " Natural flavor" replaced with exactly what the flavor is made of, I mean I'm sure spiders have a flavor, and they are natural, but I don't want to eat them if I had the choice...
Other things like Military and security issues do have reasons they can not be made public. I respect the idea behind that as long as the theory does not go too far... and EVERYTHING gets to be "classified", including why a stapler costs $8 at the office supply store, but the military one ( Identical to the office supply store, make, model, and even color) sells to the military for $45.... that crap needs to be out in the open for discussion.