executive experience

I've followed politics for a while now, and I've never heard this meme about important "executive experience" is until Sarah Palin was announced as McCain's running mate. I could be completely wrong about this, but for the life of me, I do not remember it ever being used. This is probably just a blind spot in my memory. It's just eerie to hear all the pundits suddenly talking about it as the be all/end all qualification for political office.