North Korean leader Kim Jong Un inspects a military factory in this undated picture released by the Korean Central News Agency on Friday, May 17. North Korea launched several short-range guided missiles into the sea off the Korean Peninsula's east coast May 18, South Korea's semi-official news agency Yonhap cited the South Korean Defense Ministry as saying.
Kim Jong Un visits the Ministry of People's Security on Wednesday, May 1, as part of the country's May Day celebrations.
A North Korea soldier gestures to stop photographers from taking photos from a Chinese tour boat as other soldiers look on along the North Korean bank of the Yalu River near the town of Sinuiji across the Chinese city of Dandong in Liaoning province, China, on Saturday, April 6.
North Korean soldiers gather by the docks in Sinuiju near the Chinese border on Thursday, April 4.
North Korean soldiers patrol along the Yalu River in Sinuiju across the border from the Chinese city of Dandong on April 4.
Kim Jong Un is briefed by his generals in this undated photo. On the wall is a map titled "Plan for the strategic forces to target mainland U.S."
Kim Jong Un works during a briefing in this undated photo.
North Korean leader Kim Jong Un inspects drills by the Korean People's Army navy at an undisclosed location on North Korea's east coast on March 25 in a photo from the state-run Korean Central News Agency.
Kim makes his way to an observation post with North Korean soldiers on March 25.
Kim uses a pair of binoculars to look south from the Jangjae Islet Defense Detachment near South Korea's Taeyonphyong Island on March 7.
Kim is greeted by the family of a soldier as he inspects Jangjae Islet Defense Detachment near South Korea's Taeyonphyong Island in South Hwanghae province on Thursday, March 7, in a photo from the state-run Korean Central News Agency.
Kim is surrounded by soldiers during a visit to the Mu Islet Hero Defense Detachment near South Korea's Taeyonphyong Island on March 7. North Korea has escalated its bellicose rhetoric, threatening nuclear strikes, just before the U.N. Security Council passed tougher sanctions against the secretive nation on March 7.
Kim arrives at Jangjae Islet by boat to meet with soldiers of the Jangjae Islet Defense Detachment near Taeyonphyong Island in South Hwanghae province on March 7.
Soldiers in the North Korean army train at an undisclosed location on March 6.
North Korean leader Kim Jong Un, center, poses with chiefs of branch social security stations in this undated picture released by North Korea's official news agency on November 27.
Kim celebrates with staff from the satellite control center in Pyongyang, North Korea, during the launch of a rocket carrying a satellite, in a photo released by the official North Korean news agency on December 12.
A crowd watches as statues of the nation's founder, Kim Il Sung, and his son Kim Jong Il are unveiled during a ceremony in Pyongyang on April 13, 2012. Photos from North Korea are rare, but the country was on full display in April 2012 as it celebrated the 100th birthday of Kim Il Sung.
A North Korean soldier stands guard in front of an UNHA III rocket at the Tangachai-ri Space Center on April 8, 2012.
In April 2012, Pyongyang launched a long-range rocket, which broke apart and fell into the sea. The UNHA III rocket is pictured on its launch pad in Tang Chung Ri, North Korea.
A closer look at the UNHA III rocket on its launch pad in Tang Chung Ri, North Korea.
A military vehicle participates in a parade in Pyongyang on April 15, 2012.
North Koreans wave flags in front of portraits of Kim Il Sung, left, and his son Kim Jong Il during celebrations to mark the 100th birth anniversary of Kim Il Sung in Pyongyang on April 16, 2012.
North Korean soldiers relax at the end of an official ceremony attended by leader Kim Jong Un at a stadium in Pyongyang on April 14, 2012.
Kim Jong Un applauds as he watches a military parade in Pyongyang on April 15, 2012.
A North Korean soldier stands on a balcony in Pyongyang on April 16, 2012.
North Korean soldiers march during a military parade in Pyongyang on April 15, 2012.
Soldiers board a bus outside a theater in Pyongyang on April 16, 2012.
North Korean performers sit below a screen showing images of leader Kim Jong Un in Pyongyang on April 16, 2012.
North Korean soldiers salute during a military parade in Pyongyang on April 15, 2012.
Kim Jong Un visits the Rungna People's Pleasure Ground, which is under construction in Pyongyang, in a photo released on July 3, 2012, by North Korea's official Korean Central News Agency.
North Korean soldiers listen to a speech during an official ceremony attended by leader Kim Jong Un at a stadium in Pyongyang on April 14, 2012.
Members of a North Korean military band gather following an official ceremony at the Kim Il Sung stadium in Pyongyang on April 14, 2012.
North Korean military personnel watch a performance in Pyongyang on April 16, 2012.
A North Korean controller is seen along the railway line between Pyongyang and North Pyongan province on April 8, 2012.
A North Korean military honor guard stands at attention at Pyongyang's airport during a diplomatic visit on May 2, 2001.
Kim Jong Un and North Korea's military
Kim Jong Un and North Korea's military
Kim Jong Un and North Korea's military
Kim Jong Un and North Korea's military
Kim Jong Un and North Korea's military
Kim Jong Un and North Korea's military
Kim Jong Un and North Korea's military
Kim Jong Un and North Korea's military
Kim Jong Un and North Korea's military
Kim Jong Un and North Korea's military
Kim Jong Un and North Korea's military
Kim Jong Un and North Korea's military
Kim Jong Un and North Korea's military
Kim Jong Un and North Korea's military
Kim Jong Un and North Korea's military
Kim Jong Un and North Korea's military
Kim Jong Un and North Korea's military
Kim Jong Un and North Korea's military
Kim Jong Un and North Korea's military
Kim Jong Un and North Korea's military
Kim Jong Un and North Korea's military
Kim Jong Un and North Korea's military
Kim Jong Un and North Korea's military
Kim Jong Un and North Korea's military
Kim Jong Un and North Korea's military
Kim Jong Un and North Korea's military
Kim Jong Un and North Korea's military
Kim Jong Un and North Korea's military
Kim Jong Un and North Korea's military
Kim Jong Un and North Korea's military
Kim Jong Un and North Korea's military
Kim Jong Un and North Korea's military
Kim Jong Un and North Korea's military
Kim Jong Un and North Korea's military
Kim Jong Un and North Korea's military
STORY HIGHLIGHTS
- "We just don't know the stability of their leader," Rep. Mike Rogers says
- Rogers is chairman of the House Intelligence Committee
- Analysts debate whether Kim or the North Korean military is really in charge
(CNN) -- A top U.S. congressman expressed concern about the "stability" of North Korean leader Kim Jong Un after months of provocative statements and behavior from the nuclear-armed communist state.
"You have a 28-year-old leader who is trying to prove himself to the military, and the military is eager to have a saber-rattling for their own self-interest," said Rep. Mike Rogers, the chairman of the House Intelligence Committee. "And the combination of that is proving to be very, very deadly."
North Korea launched a satellite into orbit atop a long-range rocket in December, conducted its third nuclear weapons test in February and announced earlier this month that it was abandoning the 1953 armistice that ended the Korean War.
On Saturday, it announced that it would not negotiate with the United States over its nuclear program, challenging arguments that its weapons program was a bargaining chip that might be traded away for economic benefits.
READ: North Korea: Nuclear program not a bargaining chip
Rogers, R-Michigan, told CNN's State of the Union that North Korea "certainly" has the missile capability to strike the United States. Analysts say North Korea is years away from being able to accurately deliver a nuclear weapon atop a long-range missile. But Rogers said the fact that the North is willing to openly threaten the United States with a nuclear attack "is problem enough."
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"This is very, very concerning, as we just don't know the stability of their leader -- again, 28 years old," Rogers said. "We're just not confident that we know he wouldn't take those steps."
Pyongyang disregarded numerous warnings to conduct February's test and threatened afterward that it was prepared to launch a pre-emptive nuclear strike to defend itself. The U.N. Security Council stiffened sanctions on the North after the test, with its leading ally, China, making the vote unanimous.
The North has also renewed its threats toward South Korea, warning of "strong physical countermeasures" after the sanctions vote.
READ: U.S. to beef up missile defenses
Kim is the grandson of Kim Il Sung, the founder of the North Korean state. He rose to power in December 2011, after the death of his father, Kim Jong Il. Victor Cha, a longtime North Korea analyst at the Center for Strategic and International Studies in Washington, said the North's recent actions have fueled debate about whether Kim "really is fully in charge, or whether the military is in charge."
"The three top military generals that were with him when his father died are all gone now, and we don't know what happened to them," Cha said on CNN's Fareed Zakaria GPS.
"That could be a sign of him taking control, but it could also be a sign of some real churn inside the system where some people don't like the fact that a 28-year-old is now running the country."
And Donald Gregg, a former adviser to then-Vice President George H.W. Bush and former U.S. ambassador to South Korea, said North Korean contacts he has met recently told him "that they have given up on their diplomats, and the military is now in control."
"What they want is to talk about moving from the now-disbanded armistice agreement to the creation of a peace treaty," Gregg told GPS. "That's what they want to talk about, and anyone who is willing to talk about that, they will listen to. Anyone who wants to talk about what they call the old way, which was give up your nuclear weapons and then we'll talk, is going to get nowhere."
Gregg recommended engaging the North Koreans in new talks. But Cha, a former National Security Council official in the second George W. Bush administration, said that can't be done so soon after their nuclear and missile tests, and he predicted "a very difficult period for the next couple of months or so."
"They don't want to give up their nuclear weapons. They want to be able to have their cake and eat it, too," he said. "U.S. policy for the past quarter century or so has been, 'These things are all on the table if you're willing to give up your nuclear weapons.' This is the problem. This is the dilemma right now."