Since day one of her administration, South Korean President Park Geun-hye has given Korean unification a prized position in her rhetorical repertoire.

Park’s inauguration speech, delivered in February 2013, set the tone of her tenure with a pledge to work toward an “era of harmonious unification.” The next year, in the German city of Dresden, the president fleshed out a more detailed vision, calling for greater inter-Korean cooperation to build trust and, ultimately, achieve reunification.

By all accounts, her task faces enormous political, logistical and cost-related challenges. But it must also confront a major obstacle