FBI Director James Comey will not be charging Hillary Clinton with anything, at all. She's free and clear. Well... not exactly.
...Comey's conclusion, which he insisted no politician in the Obama administration was aware of in advance, amounted to a declaration that Clinton and her aides were 'extremely careless' with their handling of classified material, but their actions did not rise to the level of a prosecution.'None of these emails should have been on any kind of unclassified system,' Comey said.'Although there is evidence of potential violations of the statutes regarding the handling of classified information, our judgment is that no reasonable prosecutor would bring such a case.. Prosecutors necessarily weigh a number of factors before deciding whether to bring charges.'
Comey is practically spelling out how to attack Hillary Clinton if you are Donald Trump or his supporters or an anti-Hillary Super PAC. The key phrase is 'extremely careless'. How is a Secretary of State acting in an extremely careless manner with state security, and
allowing enable her staff to do the same thing, remotely qualified to be president? Answer: She's not.
Donald Trump can hammer on a rigged system, as he should. But it would serve him well to twin that message with one of Hillary not being ready to be president because she couldn't even get the most basic things right at State. It's a two-pronged attack that puts Hillary heavily into a highly defensive position. The system is rigged and it's supporting a status quo candidate even though she can't get the fundamentals of security right.
That will turn off Sanders voters who believe the system is rigged. It will turn on conservative voters who don't like Hillary already but might not be quite pro-Trump. It will at lights flick on the light bulb for a lot of low information voters. Hillary cannot claim to be both innocent and competent in this matter. She's damned either way and it needs to be hammered home with voters over and over again.