Quick question: Why do you think it is that so many governments force their people to vote? Here are two of the most immediate (to me) possible answers: 1) Some political party (call it "party A") identified a large group of non-voters who, if forced to vote, would tend to vote for party A. Party A then successfully passed compulsory voting laws to gain additional power. 2) "Not voting" is actually vote of no confidence/no legitimacy in the entire political system, which all major parties view as a direct threat to their power. IMO, (2) is by far the most probable, because if (1) were the case, there would come a time where some "party B" finds an equal power benefit from abolishing the compulory voting laws, and finds an opportunity to do so. These laws would thus tend to be very unstable and uncommon. Based on this conclusion, I predict compusory voting laws will become a major political issue in the USA within the next decade, as discontent grows, and the failure and moral illegitimacy of the system becomes more and more obvious to the people who at present are most likely to vote.