Security Council's struggle to respond to Sunday's rocket launch also portends challenges for Obama's nonproliferation goals with Iran.
N. Korea's missile launch Sunday complicates the long-term strategy of the US and her Asian allies toward Pyongyang's nuclear program.
In Prague speech Sunday, the US president talked about Iran, North Korea, Russia, and how to stop the spread of nuclear weapons.
At the G-20 summit, the US, Japan, and South Korea are attempting to win backing for a Security Council resolution against North Korea.
The US has said it won't use destroyers to shoot missiles down. But they could gather intelligence.
The missile launch is believed to be a military test, though Pyongyang insists it is launching a satellite.
Did the two women cross into North Korea, or did border guards lure them over?
The move comes as South Korea and the US begin a large-scale joint military exercise.
In South Korea, which she visited Thursday, fears persist that the US will move forward on ties even if the North resists verifying disablement of its weapons.