According to the author of a RAND study on North Korean missiles, not very:

The author of the study, Markus Schiller, a missile expert at Schmucker Technologie in Germany, said in an e-mail interview that Wednesday’s launch doesn’t change his conclusions about the North’s missile capabilities or intentions.

“There is no need to reconsider any conclusions or recommendations of the report,” he said. He noted this is the country’s only success of long-range technology from five launches over nearly 15 years and was a “rocket that uses old Russian engines.”

“I would say that a North Korean cargo ship, or an airliner from Koryo Air, is more dangerous,” he added, referring to the North’s state-run airline. “If they wanted an ICBM [intercontinental ballistic missile], they have to develop a new rocket, using different technology. This would take a very long time, require a lot of work, and cost a lot of money.”

Anyway, as I said in the comments yesterday, blowing a big chunk of your limited GDP and risking even more international sanctions to do something the Soviets and Americans did a half century ago is precisely the sort of wise decision-making that made North Korea the shining beacon it is today.