Agree. But it happens all the time. Why else do you think they have those long periods of gardening leave when you leave one employer for another, or those clauses in contracts saying you will not work for a competitor in the same field for X months when you leave? (Although, I seem to recall the last one being unlawful since they are essentially stopping you earning a living).

Sometimes employers are willing to take that risk.

Do you think Ed Snowden is now more or less employable now?

His options are certainly more limited now (considering most employers could not keep him safe). That being said, I imagine his existing options would be readily available and would all pay millions.

Very true. Trust is important -- hard to win, easy to lose. Once lost, it never comes back.