I've been discussing earlier this month how game designers can make punishing players for certain things more acceptable by framing that game mechanic rather as a reward for the opposite behavior. Very frequently you can express the same thing in either a negative statement (e.g. "we don't have the full solution") or turn it around and express it as a positive thing (e.g. "we already have part of the solution").

If I look at US politics, which are even more than European politics a game of negative advertising, I think that politicians are missing an opportunity here. For example Clinton has that problem with the private e-mail server she used, and the Republicans are milking that for negative advertising as much as they can, and are pushing for more and more "investigations" into the matter for publicity reasons after the initial investigations didn't come up with the result the Republicans wanted. And Clinton is just relatively silent on the issue and is sitting it out. Huge lost opportunity there: Clinton should advertise things like: "Would you trust the government with all your secrets? Me neither!". Using a private service rather than a government one is something the Republican core voter can understand. Paint the Republican party leadership as people who are pushing for total control by the state on this issue, and they'll quickly shut up about those e-mail servers.

Of course the Brexit referendum is another great example where both sides engaged in negative advertising, trying to get voters to react out of fear of some (often imaginary) negative consequence of the other side rather than explaining the positive points of their side. The Russian revolutionary Nikolai Bukharin said that democracy is the preferred form of government of the bourgeoisie when they are fearless, but fascism is the preference when they are afraid. If politics become a game of scaremongering, right-wing populists will win that game.