Yes, this could easily become a national security problem. Anytime compromising information concerning government workers is gathered, national security is at stake as this could easily turn people working in sensitive areas. Should the citizens be worried? Other than keeping a small footprint on the net, there isn’t a lot they can do about it. That is the National Security Agency’s job, through their Signals Intelligence departments, among others.
Every major government on the globe, including ours, monitors the internet for the purposes of collecting, and processing of information and data for foreign intelligence and counterintelligence purposes. Identifying trends and weaknesses within a society, exploiting and enhancing it’s fears of conspiracy, identifying and encouraging small groups with anti-government or anarchic tendencies, etc., can be easily exploited with propaganda and psy-ops campaigns, creating yet another thorn in the side of one’s enemy. Hacking a country’s central banking system can temporarily interrupt the enemy’s markets and threaten their economy. This is called network warfare and it is very real and can be damaging to a targeted government. The job description is to be a constant nuisance to the enemy. Everybody does it.
China has become especially adept at this. The recent hacks into our major Healthcare insurance agencies has been attributed to the Chinese government. They have been able to acquire personal health information on tens of thousands of U.S. government workers and contractors which may prove compromising in that this info could be used to blackmail these people who may have their careers curtailed if certain health problems that they have been hiding from their employer is exposed.
In the Ashley Madison case, a person might divulge sensitive information to an enemy in order to keep their peccadillos from becoming public knowledge. This is a possibility our government security agencies would be remiss to ignore.