And she did know that using public email services for confidential business is against policy
If she did know, then I agree. Which would put her partially at fault.

they are spending too much time worrying about "who's fault it is" and not enough time on fixing the damage/preventing it from happening again
That's what I'm thinking as well. Now what about Yahoo running a story about an old hack? I'm still convinced this dopey kid read that article & thought it would be fun to mess with Palin's email. In my opinion, the cons far outweighed the pros of running that article.