核试验nuclear test;

　　核弹头nuclear warhead;

　　平壤Pyongyang;

　　行动过火overact;

　　严重挑衅serious provocation;

　　沉默回应muted response;

　　实施制裁impose sanctions;

　　外交边缘政策diplomatic brinkmanship;

　　引起国际社会强烈谴责spark international outrage