WASHINGTON, DC — North Korea's fifth and largest nuclear test last Friday was a wake-up call to us all.

"The tone among Korea watchers has changed. It's not funny anymore, and it's not really possible to dismiss them as a second-class missile power to be safely ignored," Thomas Karako, director of the Missile Defense Project at the Center for Strategic and International Studies, told Business Insider.

Here's a comparison of the range and capabilities of North Korea's ballistic missiles:

"The North's missile capabilities are advancing on several fronts, and both the United States and our allies in the region will have to do something about it," Karako said.

So far this year, North Korea has conducted a little more than 15 rounds of ballistic-missile tests and has fired 30 various rockets.

"The accelerated pace of missile testing represents not only a further demonstration of the North's preexisting short and medium range capabilities, but also the ambition to develop longer range and more mobile systems," Karako said.

Earlier this year, the US and South Korea agreed to deploy a THAAD — Terminal High Altitude Area Defense — battery to further defend South Korea. In conjunction with the US, Seoul plans to have the unique air-defense system operational by the end of 2017.

Meanwhile, South Korea's Defense Ministry said the rogue regime is ready to conduct an additional nuclear test at any time.

"Assessment by South Korean and US intelligence is that the North is always ready for an additional nuclear test in the Punggye-ri area," the site of the North's five nuclear explosions, Moon Sang-gyun, a Defense Ministry spokesperson, said at a news briefing.

Following the North's latest nuclear weapons test, the United Nations Security Council met to begin work on a resolution.

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