I hear you, but Chaikin wrote that as if men in other businesses ARE fully vetted. And yes, they should be. But how many turn out to be lying on their résumés and the like?
It's the same everywhere. Down in Pennyland, time after time people hire staffers or executives without even doing a background check.
The bottom line is that in politics, as in Pennyland, people believe what they want to believe. Makes no difference what the facts are.