Personally, I couldn't care less about Sanford's marital problems, though I feel sorry for his wife and kids. However, his decision to run off to Argentina, his staff giving missinformation (deliberately or not), and leaving SC without a chief executive give serious question to his ability to govern.
To be clear, his confession was forced because an intrepid SC print journalist followed a tip, did some investigating, and caught him getting off the plane in Atlanta. Her paper also had someone waiting at another aiport where Sanford could have been returing from Argentina. Who knows how this would have played out if he had been able to return without detection?
"It does me no injury for my neighbour to say there are 20 gods or no god. It neither picks my pocket, nor breaks my leg."
-- Thomas Jefferson