Runciman discussed the difficulty of how western democracies deal with long term issues and crisis on Start the Week this morning, and (further to some perhaps ill advised in-the-moment tweets) I wanted to add some thoughts on the question, and to broaden the discussion.
In a representative democracy politicians decide on matters of law and policy, and a great many of these issues, though often important to society as a whole, are insufficiently evocative to capture public interest. The balance between 'mob rule' and a more aristocratic approach to policy decisions is decided by the degree to which it affects the public as a whole, how it is treated in the media, and how easily the issue can be distilled and argued on either side (or any of the many sides, in some cases).
Take climate change. It's far easier to deny climate change than to launch into a discussion of the science, at least without grossly simplifying it to the point that you leave yourself open to serious criticism. As a result, it is easy for climate denial to gain purchase with the public, and if two political parties staked out opposite positions on that, the party which favoured ignoring climate change would gain an advantage by taking it to the public, whereas the party which favoured tackling it would gain an advantage by keeping it within Westminster.
Now that's a simplification, of course, in reality although all major parties in Westminster favour tackling climate change on paper, the degree to which they're willing to invest time and money into doing so is subject to a large number of competing concerns, and the fact that they have not brought the debate to the public does not stop sections of the media from doing so, it merely depoliticises it.
Two further examples are instructive. The humans right discussion over votes for prisoners could be viewed at two levels, either as an argument for treating different kinds of prisoners differently, according to their offense, or as an emotive issue about rights for criminals, as opposed to victims. As long as this issue was public, and not parliamentary, anyone taking the latter approach had an easier time.
This is not to say that the public are stupid, but that they have what are called 'information costs'; they are busy and don't have time to do their own research, or fact check everything they read. Simple messages work, evocative messages work better.
Similarly on the deficit, whatever your opinion of the policy it is clear that deficit reduction is easy to explain. The line about the UK's "credit card", or about small businesses cutting back is an easy one to make, and resonates with the average person. Trying to explain macroeconomis in a liquidity trap is a far harder thing to do, and the Labour party has been relegated to attempting to turn spending multipliers into a soundbyte. Their best attempt so far has been: If gordon brown is to blame for our situation, presumably he's the reason the US, Ireland, Greece etc-- with all their varied circumstances-- find themselves in crisis.
In a crisis the salient issue *must* by definition concern the public, so the side which has the simplest case to make has an advantage, irrespective as to the virtues. For this reason, when crisis hits the debate must expand to a larger constituency as per Schattschneider, and how the system responds depends on what the problem is, how well educated and responsible the politicians are, and how the media operates. Effectively, the degree to which a western democracy is technocratic or 'mob-ruled' is a dynamic equilibrium, where changing conditions shift the balance between the public sphere and a closed environment.