North Korea "could sell this technology to others, including Iran and Pakistan, who have been regular customers of North Korea's other missiles," warns Victor Cha, who analyzes the region for the Center for Strategic and International Studies.
"They still have other technological thresholds to cross (miniaturized warheads, reentry vehicle), but this was undeniably a major one."
The rocket blasted off from a space center on the country's west coast and delivered a satellite into its intended orbit, the North Korean regime said. The launch followed a botched attempt in April and came just days after Pyongyang suggested that a planned launch could be delayed.
North Korea's previous claims of successful launches have been dismissed by the United States and other countries.
But this time, a U.S. official confirmed that the object is in orbit. U.S. officials were looking into whether it is an operating satellite, the official said.
The regime's state-run Korean Central News Agency said the satellite, named Kwangmyongsong-3, was "fitted with survey and communications devices essential for the observation of the earth."
The satellite itself is probably not very sophisticated, said David Wright, a senior scientist with the Union of Concerned Scientists.
The regime showed it in April, and it was a small box with solar panels and a simple camera with some basic communication devices, he said.
He compared it to Sputnik 1, the first man-made satellite that Russia launched into space in 1957. The value lies in the launch rather than in the object that North Korea now has floating above the Earth, Wright said.
The regime doesn't "really care so much what's in it." It's a statement, Wright said.
In Japan and South Korea, people will hear about North Korea's achievement -- and will probably be struck by its power, he said.
Any show of might can help strengthen North Korea's position in international talks on numerous issues, including nuclear negotiations.
The South Korean government said the launch was confrontational and a "threat to the peace and stability of the Korean Peninsula and the world." Japan called it "intolerable."
Iran praises the launch as much of the world assails it
Iran, meanwhile, praised North Korea's move.
Gen. Masoud Jazaeri, a senior Iranian military official, expressed happiness about the launch, the semiofficial Fars News Agency reported.
"Experience has shown that independent countries, by self-confidence and perseverance, can quickly reach the height of self-sufficiency in science and technology. Hegemonic powers, such as the United States, are unable to stop the progress of such countries," he said.
China expressed regret that the launch had taken place, noting "concerns among the international community."
"We hope relevant parties stay calm in order to maintain peace and stability on the Korean Peninsula," said Hong Lei, a Chinese Foreign Ministry spokesman.
Several governments criticized Pyongyang's decision to spend hundreds of millions of dollars on its rocket program rather than on assisting its poor, malnourished population.