Russian involvement should be proven by declassifying the CIA's findings, say many on the Left. I've been arguing that, just because we take the threat seriously, we should not expose our sources and methods. Daveed Gartenstein-Ross (h/t Wretchard) points out that there is already plenty in the public space to show the involvement of Russian hacking organizations.
Even if Russian propaganda operations are at most a marginal concern vis a vis our elections, it doesn't make any sense to help them out by getting all panicky and putting everything we have in the clear. When it's dangerous, that's just when it's most important to relax.