Ilya’s [Somin's] basic argument, at least as I interpret it, runs like this: The American public is deeply ignorant about politics; this is problematic for a functioning democracy; this is unlikely to change in the future; the best and fairest way to address this is to decrease the number of functions that government performs and to encourage people to “vote with their feet.”From here.
Sean Trende at the Cato Institute, however, argues in the article linked above that while this argument makes sense, that experience has shown that voters are pretty good in practice at choosing that candidate whose position best matches their own worldviews despite ignorance of all sorts of policy and political minutiae.
Voters turn out to be good in practice at voting the right way on the issues most salient to them, in part because our two party system provides labels that are usually sufficient to root out for most voters the correct answer to what, in the ballot box, is a simple, multiple choice question and not an open ended political trivia test.
Political ignorance might be too great for direct democracy, for example, via the citizen's initiative process, to be a good idea. But, it isn't so great that a workable representative democracy is unattainable.