And what does freedom of speech have to do with trying to make sure an intelligence agency isn't hiring double agents?
Congress shall make no law respecting an establishment of religion, or prohibiting the free exercise thereof; or abridging the freedom of speech, or of the press; or the right of the people peaceably to assemble, and to petition the Government for a redress of grievances.
http://constitution.findlaw.co...
This is not a "yelling fire in a crowded theater" situation involving immediate clear harm. Rather, it's about freedom of the press in exposing polygraphy as a pseudoscience that is as valid as drowning women to find out if they are witches. The polygraphy book does this by showing exactly how polygraphy doesn't work.
The Government is using its substantial power to suppress this information contrary to the mandatory dictates of the First Amendment. When the US government ignores the Constitution, that is a far graver threat to America and its purported values than any terrorist or double agent could ever achieve, because it decouples the massive power the Feds have from any limitations at all -- it is in essence, the destruction of America from within.
Think about it like this: There is USA, the place, and America the vision as embodied by our Constitution. Given the US Federal Gov's all-out assault on the Bill of Rights, it's fair to say that _it_ is the greatest threat to the freedoms we as Americans are said to hold dear, in favor of protection of USA the place. It is of course a totally dubious assertion that the pseudoscience of polygraphy is even effective at protection of USA the place, but even if it was a valid technique, we should be asking if we want to have a Federal Government that is totally unrestrained in its exercise of power. If that is where we are heading, we should just acknowledge that post-constitutional USA is just another authoritarian dictatorship, and quit giving lip service to being a constitutional republic that values freedom and justice. It would save a lot of people a lot of prison time to know we are just another China, and to keep their mouths shut.