They were NSA employees and IBM engineers. There are no blanket prohibitions on travel for NSA folks, although I believe there are more or less 'don't go there'

They were NSA employees and IBM engineers. There are no blanket prohibitions on travel for NSA folks, although I believe there are more or less 'don't go there' advisories about specific places. I also imagine there are folks there who know things that put them in special travel categories. I don't think the IBMers had any special conditions imposed on them.