Tension Rising After North Korea Attacks

As uncertainty and tension quickly rise in the wake of Tuesday's attack on South Korea's Yeonpyeong Island, U.S. warships have been sent to the region as a show of solidarity with the nation, as well as a strong force against North Korean armed forces and their leader Kim Jong-Il.

"It is a long-planned exercise," said Adm. Mike Mullen, chairman of the U.S. Joint Chiefs of Staff.

"That said, it is meant to send a very strong signal of deterrence and also work with our very close allies in South Korea," Mullen said on CNN's "Fareed Zakaria GPS."

North Korea has been viewed by U.S. officials as an area of concern for most of the past decade due to their public push to proliferate a nuclear weapons program, which drew much ire in 2007 after the communist nation tested several nuclear devices, including five short-range missiles which were launched by the North into the sea off its eastern coast, in violation of U.N. resolutions.

Those tests pushed South Korea to join the Proliferation Security Initiative, a global effort that aims to stop trafficking of weapons of mass destruction, their delivery systems, and related materials to and from states and non-state actors of proliferation concern.

Created by President George W. Bush in 2003, the Initiative includes more than 90 countries that agreed to interdict suspicious cargo ships.

The day after South Korea's decision to join, North Korea claimed that the South had nullified the agreement they had made in 1953 -- the armistice that ended the Korean War by barring either nation from imposing a naval blockade -- by joining the anti-proliferation effort.

The North also said it would not respect the legal status of five islands on the South's side of the line, which may have included Yeonpyeong.

Over the past 18 months, however, a push has been made by North Korean officials for more diplomacy with South Korea and the U.S.

Having been rebuffed in those efforts, Tuesday's attacks could be viewed as an effort by North Korea to show what consequences its southern counterparts -- and their allies -- could face if they are ignored much longer.