If I'm understanding you, you're wondering what to do with the information, and comparing it to an identical situation where you don't have the information.

You're right that an early-warning system hasn't been developed. We have no way of knowing what the NSA will decide to analyse after the fact. Indeed, we do not know if an asteroid will hit the earth tomorrow. At one level, there is a limit to our ability to predict the future.

So it's up to the individual. We self-censor, or don't. The chilling effect of the knowledge of surveillance is well documented. Are you making a point that thinking you're being spied upon is more damaging than any fallout of the actual spying?