Walker was kaki if I remember correctly I don't remember if his son was. The Walker's treason was actually a good thing in the end. It made the Navy re-evaluate security clearances. I was working on subs at Pearl at the time. Mine actually went up after the re-evaluation, but most went down to only confidential. It got really stupid, right afterwards. If I had work on a Boomer, I already had the clearance, but I had to submit a temp clearance for each one of my crew.
With my clearance, I got all the jobs for our shop for Boomers. It took well over a year for the DoD to do the proper background checks for the other personnel.
I really find it a bit ridiculous, maybe surprised is a better word, that so much about a nuke power plant is still classified. I can see why a large part of the primary side is classified......core, pressurizer structure and size of pumps and piping. You can derive power outputs and functions. Secondary side is not really different than a conventional plant.
That being said, there is a plethora of things that can be derived from simple material and construction specs. That's just the boat itself, weapon and detection systems are quite obvious.
Times and tech change. It's good that they changed phones with on duty. It is a security risk. It really should have been across the board, with only limited exceptions that have been thoroughly researched, not a blanket SOP for so-called management.