The blame on security at Los Alamos National Laboratory should be blamed on LANL's own upper administration. These laboratories are pretty much on their own as far as security goes. Security is only as good as the administration in charge.
This particular incident, I believe, was more of an inside job and had nothing to do with security per se. Engineers, mathematicians, physicists and chemists employed at these laboratories are responsible for securing any programs, documents or research data they originate.
As a former employee (25 years) at the Lawrence Livermore National Laboratory in Livermore much like Mr. Bartholomew (whose letter to the editor was published in the) Payson Roundup, Tuesday, June 27 I had access to some laboratory areas. Unlike Mr. Bartholomew, I found that security was pretty tight. True, you could roam in some areas called the green areas, but don't try to get into the red areas without that certain mark on your badge. There is no way you could get into a secured area that is only accessible through security booths with security guards or photo indentification access.
The LANL incident was an LANL administration problem, and only that. The people responsible are, of course, the people working there. These individuals had (their) backgrounds checked and double checked before access was given to them in such sensitive matters.
In my opinion, they turned coat after security clearances were given. Greed was the motive money, money, money.
Hopefully they did not get away with any sensitive material that will jeopardize our national security. When guilty parties are discovered, they should be dealt with accordingly.