From Brazil to El Salvador, from Uruguay to Ecuador, from Chile to Venezuela, left-of-center or hard-left parties and leaders have recently been voted into office. Some of these have performed splendidly (Chile, Brazil and Uruguay); others, so-so (Argentina, Ecuador and El Salvador); while others are making a mess of things (Venezuela, Bolivia, Nicaragua and, as always, Cuba). But there is a new wave emerging, one that is as welcome as the appearance of a modern, moderate, market-oriented democratic and globalized center-left. That is a democratic, socially concerned center-right whose policies can often be mistaken for those of the center-left. The two best examples of sitting governments in this regard are in Chile and Colombia. How they differ from each other is leadership. Juan Manuel Santos of Colombia runs a still partly dysfunctional country — magnificently. Sebastián Piñera of Chile runs a country that operates like clockwork — mediocrely. Chile is Latin America’s success story. Its economy is thriving and, in 2010, it finessed a democratic transition from 20 years of center-left government to center-right rule without major mishaps. President Piñera is a thinking man’s businessman and won kudos last year not only for overseeing the rescue of 33 trapped miners but also for using the moment to push overdue labor reform. Yet today Chile is fed up: Piñera has the lowest approval ratings of any chief executive in the hemisphere. His governing style too has contributed to his unpopularity: a tendency to micromanage, perhaps born of the hubris of an extraordinarily successful businessman, combined with his technocratic leanings. That has not sat well in a nation where the political elite has traditionally been competent, honest and respected. If copper prices do not continue to fall, Chile should overcome its current travails. Piñera will then be a fair-to-middling one-term President (consecutive re-election is forbidden by law). The contrast with Colombia, where Santos was elected President last year, is remarkable. Like Piñera, Santos was originally a center-right politician. Both men are patrician, with business experience; both hold degrees from the U.S. and speak perfect English. But Colombia and Santos are on a roll. He and his army have had tremendous recent success against the FARC guerrillas, a group that has been fighting the government for 40 years. With the killing of FARC commander Alfonso Cano on Nov. 4, the guerrillas have, for practical purposes, no leadership. Just before his army got Cano, Santos delivered on one of his most controversial campaign promises: dissolving the feared, corrupt and intrusive intelligence service known as DAS, and creating a new security-and-intelligence agency from scratch. How squeaky-clean the new one will actually be is anyone’s guess, but getting rid of the old was absolutely necessary. Colombia also finally got what it had been seeking for more than five years: a free-trade agreement with the U.S. Human-rights activists felt that under former President Alvaro Uribe, the country’s record did not warrant a trade deal and opposed awarding it to Bogotá, first under President George W. Bush and during the first three years of the Obama Administration. It has not hurt Santos that he has forged a trustful, though arm’s-length, relationship with groups such as Amnesty International and Human Rights Watch, which held its annual board meeting in Colombia in October. Indeed, Santos persuaded his country’s legislature to pass the Victims and Land Restitution Law to make amends to the 3 million to 4 million people displaced during Colombia’s 40-year war. No one else in Latin America has ever attempted anything on this scale. Santos’ main challenge consists of reducing Colombia’s dramatic inequality — the real root of its wars — as well as the ramshackle nature of the country’s infrastructure and its disastrous education system. While the country has enjoyed sustained economic growth over the past decade, it still lags far behind nations like Chile, Mexico, Brazil and Uruguay in almost every social and economic indicator. But Santos’ Colombia is moving in the same direction as those countries: broadening its middle class, consolidating its democracy, growing its economy. And, so far, it seems to have one important advantage: leadership. The countries lucky enough to have it do better than those that don’t.