Proponents offer three reasons in favor of mandatory voting. The first is straightforwardly civic. A democracy can’t be strong if its citizenship is weak. And right now American citizenship is attenuated — strong on rights, weak on responsibilities. There is less and less that being a citizen requires of us, especially after the abolition of the draft. Requiring people to vote in national elections once every two years would reinforce the principle of reciprocity at the heart of citizenship.

The second argument for mandatory voting is democratic. Ideally, a democracy will take into account the interests and views of all citizens. But if some regularly vote while others don’t, officials are likely to give greater weight to participants. This might not matter much if nonparticipants were evenly distributed through the population. But political scientists have long known that they aren’t. People with lower levels of income and education are less likely to vote, as are young adults and recent first-generation immigrants.

Changes in our political system have magnified these disparities. During the 1950s and ’60s, when turnout rates were much higher, political parties reached out to citizens year-round. At the local level these parties, which reformers often criticized as “machines,” connected even citizens of modest means and limited education with neighborhood institutions and gave them a sense of participation in national politics as well. (In its heyday, organized labor reinforced these effects.) But in the absence of these more organic forms of political mobilization, the second-best option is a top-down mechanism of universal mobilization.

Mandatory voting would tend to even out disparities stemming from income, education and age, enhancing our system’s inclusiveness. It is true, as some object, that an enforcement mechanism would impose greater burdens on those with fewer resources. But this makes it all the more likely that these citizens would respond by going to the polls, and they would stand to gain far more than the cost of a traffic ticket.

The third argument for mandatory voting goes to the heart of our current ills. Our low turnout rate pushes American politics toward increased polarization. The reason is that hard-core partisans are more likely to dominate lower-turnout elections, while those who are less fervent about specific issues and less attached to political organizations tend not to participate at levels proportional to their share of the electorate.