North Korea has found itself increasingly isolated. China, its most important ally, drafted the U.N. sanctions with the U.S. and expressed unusual disappointment when Pyongyang announced last week that it was restarting a plutonium reactor to produce more nuclear-bomb fuel.
Russian President Vladimir Putin, during a visit to Germany, praised the U.S. for postponing a missile test in California that had been set for this week, in the name of lowering tensions. Putin said at a press conference that a conflict on the Korean Peninsula would make the nuclear disaster at Chernobyl "look like a children's story."
The North's threats against the United States are widely dismissed as hyperbole. North Korea is believed to have a handful of relatively crude nuclear weapons, but analysts say they've seen no evidence it can build a warhead small enough to put on a missile that could hit the U.S. mainland. A direct attack on the U.S. or its allies would result in retaliation that would threaten the existence of the ruling Kim family in Pyongyang, but there are fears the North could launch a smaller-scale attack.
Another possibility is a fourth nuclear test, or a missile test.
The South Korean defense minister said Thursday that North Korea had moved a missile with "considerable range" to its east coast, possibly to conduct a test launch. His description suggests that the missile could be a Musudan missile, capable — on paper at least — of striking American bases in Guam with its estimated range of up to 4,000 kilometers (2,490 miles).
Pyongyang's warning to diplomats prompted South Korean President Park Geun-hye's national security director to say Sunday that North Korea may be planning a missile launch or another provocation around Wednesday, according to presidential spokeswoman Kim Haing.