I think people should know the history of their own country as it happens and not 30 years after the event.
I know some amendments to this were made recently but far too much of what is done in our name is kept secret for too long. The 30 year rule can of course be extended so some documents, for instance those dealing with high ranking Nazi sympthizers in British society in the 1930's, are still classified.
Why is this idea important?
I think if someone in power if up to no good the public should no about it whilst we are in a position to vote them out of office, not hear about it long after they are dead.
Only those with something to hide should oppose this.
We have the right to know the truth.