The United States has a quite good governing system, but certainly a far-from-perfect one. One of its shortcomings is the impact of the primary elections on parties' policy positions. Let me explain.
Voter turnout in primaries or at caucuses is a fraction of turnout in the November election. This would not be a problem if those who show up for the primary were a random sample of November voters ... but they are not.
Who turns out in primary elections or caucuses? Answer: the most highly motivated partisans, normally those preferring the most extreme versions of the party's policy positions. The most left wing Democrats, the most right wing Republicans are who is heard from in primaries.
That fact becomes a problem when several individuals seek the party's nomination. In order to prevail in the primary the aspirant needs to (seem to) take extreme positions appealing to the party's zealots.
Once people get their party's nomination, it is customary for them to (if possible, subtly) move their policy profile back toward the center, away from the radical fringe. The hope is to appeal to independents who very likely do not hold extreme views.
New York magazine's Jonathan Chait fears this year's crop of Democrat aspirants have forgotten the eventual need to tack back toward the center. Donald Trump should hope Chait is correct. Hat tip to RealClearPolitics for the link.
