Lol, 
this sounds like in the movies, although the reality of life is stranger than fiction. how many agents do you think North Korea have??? Kim isn't stupid to risk the life of his kin by sending them to U.S. for some minor attacks on the U.S. soil.
Kim have millions of zombie soldiers ready to do anything he will order and ready to lose lifes for him. this sounds like in the movies, although the reality of life is stranger than fiction. how many agents do you think North Korea have??? Kim isn't stupid to risk the life of his kin by sending them to U.S. for some minor attacks on the U.S. soil. Not so easy to destroy the building. Required engineering calculations to know exactly where to lay the explosives. In addition now the buildings of a lot of cameras.
North Korea have developed ICBMs and nuclear bombs. So, do you really think they don't have enough knowledge how to demolish buildings?! 