So you're suggesting that every candidate to an election should  undergo a test to detect potential sociopathy and that those whose result is positive should be barred from running? I suppose this should apply to any position involving some power, be it political, economical or other...

This raises a few questions:

• at what level of power should the testing start?
  
• as you said there is "a continuum from simple stupidity and lack of awareness at one extreme to outright clinical personality disorder ", wher should be the threshold and who would decide about it?
  
• what should be done with those who are identified as sociopaths? Should they wear a badge in order to warn other people about them?
  
• what about the false positives?

   

"People only accept change when they are faced with necessity, and only recognize necessity when a crisis is upon them." - Jean Monnet