Firstly there is nothing to be gained by beating the keycode out of him, or even obtaining it, the government would be interested only in preventing that information from existing. If there is something truly juicy in the insurance file he would have definitely sent the key to the people within the government, so that they could see for themselves what was at stake. If he didn't do that, then it would appear to them to be a bluff. (its like hiding a gun in your pocket, if you refuse to take it out and show people its a gun, then they'll just figure its a banana)
Secondly he has stuck himself into a bad situation, where (assuming that he's got something important in the insurance file) he makes himself criminal by releasing it, and is then guilty of what he claims to be innocent from. Any government prosecution can be dragged out, and englaciated to ensure that there is never a moment of high energy that would stimulate the sudden release of this information. (its the idea of a rape whistle being only useful when you are suddenly attacked, if someone did the same thing extremely slowly, you would never know at what point you should start blowing your whistle(double paren i know, but yeah its a strange example)).
Thirdly, towards aqizzar's idea of there being no legal secrets, to a certain point that is how the US government operates. There is no legal repercussions for simply knowing something you shouldn't. You can't be arrested, or convicted of knowing too much. For people who are granted clearance to something, and then violate that trust, there are legal issues, as I think there should be. People lose sight of the fact that government is society, if you pursue and then betray your society's trust, it is society's prerogative to have punishment and deterrents. If one person's actions are to the detriment to society at large, they have given up their place within it. (I guess i would see this as equivalent to white collar crime, no one has had physical harm, but it weakens society to allow it.)
And finally, I always find it funny how conspiracy theorists think that the government is abysmal at everything, except for misleading the public, at which they are magical men that can do as they please with impunity throughout the world, and they are taking a personal interest in YOUR life! Anyone who has worked with or for the government knows that there is no broad hidden government agenda, and that generally speaking the right hand doesn't know what the left hand is doing... ever..
Thats not to say that government can't be effective, or good, simply that the modern american government is too large to have the type of cohesion that would be necessary to carry out a conspiracy. (many millions of people would have to be in on it) The innane subject matter which has been released is a pretty good showing of how inconsequential government secrets really are. If there was something big he could run up the banner, some sort of vast corruption or malfeasance, he would have already. The insurance file is almost certainly simply damaging to US security