Ex-Defense secretary says North Korea is 'one of the most treacherous spots on the planet'

US at high state of readiness against North Korea: William Cohen

North Korea and its supreme leader Kim Jong Un pose one of the biggest threats to the world, former Defense Secretary William Cohen told CNBC on Friday.

"I would put that as one of the most treacherous spots on the planet right now," Cohen told "Squawk Box." "[Kim Jong Un] could take action and do something, either by miscalculation or intentionally, that would cause an overreaction by us and our allies in the region."

On Monday, North Korea fired four nuclear-capable ballistic missiles toward the Sea of Japan, three of which landed in Japan's exclusive economic zone. The United States responded by deploying defensive THAAD missiles in South Korea. elevating tensions even more, including with China.

Cohen, chairman and CEO of The Cohen Group, said North Korea could seize on the court-ordered removal on Friday of South Korean President Park Geun-hye from office because of a corruption scandal.

"I suspect that Kim Jong Un will try to exploit the confusion at the moment," Cohen said, but added that the countervailing forces to his potentially rash military actions are in place.

"Our military has certainly been in touch with the Republic of Korea military, so I think from a security point of view, we're at a high state of readiness. And if the North Koreans try and do anything that would be precipitous, I think the South Koreans and the U.S. and the Japanese will all be ready to confront that," he said.

Trump's military spending pledge

Stateside, Cohen commended President Donald Trump's call to increase defense spending and said military and intelligence officials are forecasting some of the greatest threats the United States may see in the near future.

"We used to call it NBC — nuclear, biological, chemical. To that you add cyber. So these are the kinds of major existential threats that we can face," Cohen said. "How are we prepared for that?"

Cohen mentioned the president's proposal to add up to 90,000 troops to the military to prevent fatigue from multiple redeployments, but said it would be expensive to fulfill.

"It's $1 million a soldier. So if you're talking 70,000 to 90,000 more troops, that's a pretty big price tag," Cohen said. "Then you're getting to the hawks on the budget side versus the hawks on the military side, so [there's] a long way to go here before we decide exactly how much is going to be devoted to more military spending."

Cohen, a Republican who served as Pentagon chief under President Bill Clinton, also suggested that budget officials and military authorities should work together to find areas where costs can be safely transferred to the private sector.

In light of recent information leaked from the CIA, Cohen said it was safer to leave private sector involvement limited to nonsecure roles.

"You wouldn't put things of any security into the private sector," he said. "You might put, for example, housing, electrical grids on bases, other types of services that could be delegated to the private sector without letting contractors into your secure systems."

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North Korean military participates in the celebration of the 70th anniversary of the founding of the ruling Workers' Party of Korea in Pyongyang on October 12, 2015.
KCNA | Reuters