The 2016 US presidential election is likely unusually important, because Trump seems unusually likely to damage global coordination in ways that increase the risk of major wars – and to damage US political norms in ways that are likely to accelerate the decline of discourse and governance.
This is also an election in which the libertarian candidate has been unusually viable because he has any experience at all as a major government figure – despite his apparent lack of interest in the sorts of things a president needs to know about, such as other countries. Many people also want to register a protest vote with Green Party candidate Jill Stein, since they find Hillary Clinton's respectable establishment liberal misconstruals of the true and the good objectionable, and prefer disrespectable anti-establishment left-wing misconstruals of the true and the good.
Many people agree that Trump is terrible and it would be much less bad if Clinton wins, but some people prefer a third-party candidate and are unwilling to simply back the lesser of two evils. Some people end up favoring a vote for Clinton on net; others favor a third party vote. Both types are distributed over many states.
A protest vote has the same value anywhere. Federal funding also becomes available for any party that gets more than 5% of the popular vote – and it seems like Johnson's share of the vote could pass that threshold. On the other hand, due to the US electoral college system, the cost of forgoing a Clinton vote has very different effect depending on which state you're voting in. In a "safe state" overwhelmingly likely to go to one of the two major candidates, your vote has very little effect on the outcome of the election. But in a "swing state" where the outcome is more in doubt, your vote has a comparatively large effect on the outcome. Scott Aaronson points out that this distinction creates the opportunity for gains from trade, and has been promoting the idea of vote-swapping in order to reconcile these interests. The idea is that one or more Clinton supporters in safe states pledge to vote for a particular third-party candidate, in exchange for a third-party voter pledging to vote for Clinton.
In a one-to-one swap, this keeps third party national percentages the same, but increases the chance the swing state goes for the desired candidate. This is enough to yield gains from trade if both sides share a preference for one major-party candidate over the other. But even if that's not true, a many-to-one swap can still create gains from trade, by increasing both the chance that the desired major-party candidate wins, the third-party candidate's share of the vote total.
One of my friends recently suggested that we can't trust this system not to be gamed by Trump voters. I think that this is mistaken. Continue reading →