Colombian President Juan Manuel Santos gave an inspiring speech at the United Nations General Assembly this week. Secretary-General Ban Ki-moon and member states have lauded his visionary commitment to ending Colombia’s half-century civil war.

But sitting down to negotiate, as he proposes, with the Revolutionary Armed Forces of Colombia (FARC) insurgency, a group with deep ties to narco-trafficking, kidnapping and on the US terrorist watch list, is not without a high degree of political risk.

The United States, which has spent more than a decade supporting the Colombian Armed Forces in its mission to defeat the FARC may be understandably ambivalent about negotiating a peace agreement with the guerrilla group, and the ensuing legitimacy and eventual immunities an accord would provide.

Yet the most effective way to support its closest ally in the region is for the United States to define demonstrable support for President Santos’ efforts for peace.

Colombia’s current president has taken important steps to re-balance the state more firmly in the center than his predecessor, Alvaro Uribe. Failure at the negotiating table is likely to trigger an electoral reaction not unlike the one that swept Uribe to power as President Andres Pastrana’s efforts to negotiate at Caguan floundered.

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