The White House condemned what National Security Council spokesman Tommy Vietor called “yet another example of North Korea's pattern of irresponsible behavior.”
“The United States remains vigilant in the face of North Korean provocations and fully committed to the security of our allies in the region,” Vietor said in a statement. “Given this current threat to regional security, the United States will strengthen and increase our close coordination with allies and partners.”
Vietor said the international community must “send a clear message that its violations of U.N. Security Council resolutions have consequences.”
China expressed its unhappiness but called for a moderate response from the United Nations.
“We express regret at (North Korea's) launch in spite of the extensive concerns of the international community,” Foreign Ministry spokesman Hong Lei told reporters. He added that China “believes U.N. Security Council reaction should be prudent and moderate and conducive to maintaining stability and avoiding escalation of the situation.”
Hong said dialogue and negotiations are the way forward.
North Korea's Foreign Ministry accused the U.S. of overreacting to the launch “out of hostile feelings.”
“We hope that all countries concerned will use reason and remain cool so as to prevent the situation from developing to undesirable direction,” the official Korean Central News Agency quoted a ministry spokesman as saying. The spokesman said the country will “continue to exercise our legitimate right to launch satellites.”
But North Korea also defends its need to build nuclear weapons, citing the U.S. military threat in the region, and rocket tests are seen as crucial to advancing its technology.
Pyongyang is thought to have a handful of rudimentary nuclear bombs. It followed up a failed 2009 launch with a nuclear test, and announced it would begin enriching uranium, which would provide a second source of atomic material.
Experts believe the North lacks the ability to make a warhead small enough to mount on a missile that could threaten the United States, but Wednesday's launch marks a milestone in its decades-long effort to perfect a multistage, long-range rocket capable of carrying such a device.
This launch will help the North Koreans map out what kind of delivery vehicle they would need for a nuclear warhead, said retired Air Force Col. Cedric Leighton, a weapons expert and intelligence analyst.
There are concerns as well that Pyongyang may sell its technology to other nations such as Iran, which has rockets bearing a striking similarity to those made by North Korea, according to the James Martin Center for Nonproliferation Studies.
A senior Iranian military commander, Brig. Gen. Massoud Jazzayeri, congratulated North Korea on the successful launch on Wednesday, according to the semiofficial Fars News Agency.
Chae Yeon-seok, a rocket expert at South Korea's state-run Korea Aerospace Research Institute, said North Korea is now likely to focus on developing bigger rockets with heavier payloads. “Its ultimate aim will be putting a nuclear warhead on the tip.”
For North Koreans, Wednesday's launch caps a heady year of milestones: the centenary of the birth of Kim Il Sung, the nation's founder, and the inaugural year of leadership under his grandson, Kim Jong Un. And on Dec. 17, North Korea will mark the anniversary of the death of leader Kim Jong Il.
“How happy would our General (Kim Jong Il) have been,” Pyongyang resident Rim Un Hui said. “I'm confident that our country will be stronger and more prosperous under the leadership of Kim Jong Un.”