This creates something of a catch-22. The voters who are least well served by the system — such as the poor or African-Americans or Hispanics — feel that their votes don’t matter, and therefore are less inclined to vote. This is not necessarily because they aren’t paying attention. It’s often because they are paying attention, and recognize that the political system does not care about them. But by not voting, they ensure that the system is even less responsive. This in turn alienates them further — and so on.

Non-voters aren’t foolish or ignorant. They are making reasonable, even informed choices about the effort of voting versus the power of their votes. The individual reality of disempowerment creates rational individual choices. And those rational choices, unfortunately, contribute to further collective disempowerment.

Compulsory voting would interrupt this cycle. Suddenly, voting would be less costly than not voting, and as a result, many more people would go to the polls. And those new voters would very likely have a strong effect on public policy. Anthony Fowler, a professor at the Harris School of Public Policy at the University of Chicago, told me that in his research into Australia’s voting patterns, “compulsory voting increased the average vote share of the labor party by about 9 percentage points in state assembly elections.” Further, he said, “compulsory voting appeared to significantly increase pension spending, a major policy goal of the working class.”