Well, the New York Times recently asked the experts -- and it's not, uh, rocket science. Er, wait -- actually it is...
According to the experts 1) it's harder than it looks and 2) despite the setback, we shouldn't underestimate the North Korean threat:
The Hard Part: Hitting a Target by Rand Simberg, a recovering aerospace engineer who blogs about space, politics and the future at Transterrestrial Musings. Simberg writes, "It is one thing to be able to send the upper stage of a missile a few thousand miles. It is another to guide it to hit a target."
‘Primitive,’ but Dangerous, Skills by John Pike, the director of GlobalSecurity.org, a military information Web site. Pike writes:
There is a tendency to disparage the North Koreans (as well as Pakistanis, Iranians and Indians) as ignorant peons whose weapons skills are consistently derided as “primitive.” While this latest test will fuel the “ignorant peon” school, it should not.Be sure to read their entire responses.
North Korea’s low yield nuclear test in October 2006 was derided as a failure, because it did not replicate the multi-kiloton yield of America’s first nuclear test. It did, however, coincide with the sub-kiloton tests of the fission trigger for a hydrogen bomb. The “ignorant peon’” school tells us that North Korea’s “primitive” atomic bombs are too big to put on missiles. But possibly North Korea’s hydrogen bombs are easily fitted on missiles.
Here's a video simulation of what the North Korean satellite launch was supposed to look like, along with possible paths and tracking stations: