When South Korean President Park Geun-hye touted the benefits of Korean reunification in a closely-watched speech early last year, the language she chose turned a lot of heads: the word daebak was plucked straight from teenage slang, translated as "jackpot" or "bonanza."

But if Ms. Park's lingo was meant to reignite excitement among South Korea's distracted youth in seeking an end to the division of the Korean peninsula, there doesn't seem to be much evidence that it's working.

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