'Wild card' Trump heads into North Korea's line of sight

In the South Korean capital Seoul, Trump will find people who have lived with that reality for decades. 

"It's crucial for Trump to show that he's willing to defend and protect South Korea because there's a lot of questions and concerns on the part of South Koreans about his commitment to that alliance, and that has fed fears here in South Korea that they may be abandoned," said Jean Lee, a global fellow at the Wilson Center and former Pyongyang bureau chief for The Associated Press. 

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