(CNN) -- The recent news developments in North Korea, including last week's shelling of a South Korean island, illustrates a growing instability that "could be very dangerous," the U.S. military's senior ranking officer said in an interview with CNN's Fareed Zakaria.
North Korean leader Kim Jong-Il has a country "that's starving its people, whose economy is absolutely dreadful. And he continues to take actions -- and I think very deliberate actions -- to destabilize a region. ... That could be very dangerous for all of us, including -- not just the regional players, although I think, certainly, China has a great deal at stake with stability," Adm. Mike Mullen, the chairman of the Joint Chiefs of Staff, said in an interview on "CNN's Fareed Zakaria GPS" to air Sunday.
Mullen said the artillery exchange -- along with the deadly sinking of a South Korean ship and the recent revelation of a uranium enrichment facility in North Korea -- were part of Kim's plan.
"What happened with the killing of the 46 South Korean sailors, what happened with the development of the uranium enrichment facility, as well as, obviously, the artillery incident ... there are many that believe this is part of [Kim Jong-Il's] posturing for the succession of his young son," Mullen said. "But I believe his main focus is to continue to develop nuclear weapons, to continue to get the world's attention and to continue to try to move himself up to a level that is regarded as a, you know, sort of a world player."
During the wide-ranging interview, Mullen also addressed Afghanistan, as well as Wikileaks' intention to release more government documents.
Mullen said a draw down of U.S. troops in Afghanistan in 2011 "will be based on a recommendation from General (David) Petraeus and he will make that based on conditions on the ground. We don't know from what province and we don't know how many," he said.
"All of that said, every indication that I can see is there certainly is going to be a substantial number of allied troops -- U.S. and allied troops -- in Afghanistan after July 2011," he added.
Mullen said the leaking of documents by Wikileaks endangers the lives of U.S. troops.
"What I don't think those who are in charge of Wikileaks understand is we live in a world where just a little bitty piece of information can be added to a network of information and really open up an understanding that just wasn't there before," Mullen said. "So it continues to be extremely dangerous. And I would hope that those who are responsible for this would, at some point in time, think about the responsibility that they have for lives that they're exposing ... and stop leaking this information."