Another factor may also be at play: The launch took place ahead of national elections in Japan on Sunday and in South Korea on December 19. North Korea is a crucial foreign policy issue in both of those countries.
The rocket took off Wednesday morning and flew south over Japan's Okinawa islands. There were conflicting reports about how many parts fell into the sea.
A launch had seemed unlikely to take place so soon after North Korea announced Monday that it was extending the rocket's launch window into late December, citing technical issues with an engine.
Previous attempts by the North in 1998, 2006, 2009 and April of this year failed to achieve their stated goal of putting a satellite into orbit and provoked international condemnation.
The rockets launched in 1998 and 2009 flew for hundreds of kilometers but didn't succeed in deploying satellites, other countries and experts said at the time. North Korea nonetheless insisted that both satellites did reach orbit, with KCNA reporting that they were transmitting "immortal revolutionary" songs back to Earth.
The 2006 launch failed soon after takeoff and wasn't reported by state media.
In April, the North Korean regime invited members of the international news media, including CNN, into the country to observe the preparations for its planned launch. But the strategy backfired when the rocket broke apart shortly after blasting off. On that occasion, state media took the unusual step of admitting the launch's failure.

