The American People should know what our government is doing in ALL but the most sensitive and legitimately secret things. Names of agents, precise capabilities of leading edge weapons, order of battle, intelligence that would OBVIOUSLY give away its source. Other than that, let the people know.
If it CAN be destroyed by the truth, it SHOULD be destroyed by the truth. Papers don't need to know the date of the invasion, but they should damned well know the casualties, the occasions where we do something wrong, and where things aren't going as planned.
Nixon was more concerned about the leaks themselves and their impact...not so much about what it showed. Back when the Nations security came first....