The new conventional wisdom in the aftermath of the 2012 elections is that Republicans face two challenges: first, that the United States is no longer a center-right nation, but a center-left one; second, that the country’s demographic shift away from whites will make it tougher for Republicans to win votes. The proposed solution is that Republicans must compromise on the party’s core policies, from immigration to taxation to social issues. The conventional wisdom is wrong. I once worked in South Africa for a centrist party, the Democratic Alliance, which faced the same challenges as Republicans do, only far more extreme....