It is apprehended, that arbitrary power would steal in upon us, were we not careful to prevent its progress, and were there not an easy method of conveying the alarm from one end of the kingdom to the other. The spirit of the people must frequently be rouzed, in order to curb the ambition of the court; and the dread of rouzing this spirit must be employed to prevent that ambition. Nothing so effectual to this purpose as the liberty of the press, by which all the learning, wit, and genius of the nation may be employed on the side of freedom, and every one be animated to its defence. As long, therefore, as the republican part of our government can maintain itself against the monarchical, it will naturally be careful to keep the press open, as of importance to its own preservation.
Hume, Of the Liberty of the Press. If only the press worked like that; it seems obvious that we don't really get "all the learning, wit, and genius of the nation" employed to defend freedom, or to do anything, for that matter. But we still do get alarm from coast to coast, I suppose.