Obama, aan de zwaarst bewaakte grens ter wereld, waarschuwt N-Korea

US President Barack Obama (L) looks through binoculars towards North Korea from Observation Post Ouellette during a visit to the Joint Security Area of the Demilitarized Zone (DMZ) near Panmunjom on the border between North and South Korea on March 25, 2012. Obama arrived in Seoul earlier in the day to attend the 2012 Seoul Nuclear Security Summit to be held on March 26-27. AFP PHOTO / SAUL LOEB AFP