Is our government going to alert those who's social security number was stolen?

CPT (Join to see). To be honest, I doubt that the government will be able to notify many of those affected. Since much of it involves background checks over many years and each time we had to list different references and some of those references were asked to provide other references, etc. The government may well have current information on the location and contact information for all of its current employees and many of its former employees and contractors; but, it is unlikely it keeps records on the hundreds of thousands if not millions of people who served as references whose information was compromised.

Aren't they supposed to by law?

I seriously hope so, the last time this had my SSN on it, I got a year free credit monitoring! Lets hope we get notified just to be aware and that we can somehow prevent it from happening again. As for the penalties for clearances and the like, I was affected worse by the previous spouse than the thief of my PII.