The US and South Korean militaries will join together for a final military exercise to close out a heated 2017 with F-22 and F-35 stealth jets training right off North Korea’s borders.

The exercise, called “Vigilant Ace,” will run from December 4-8 and involve 12,000 military personnel between the US and South Korea, as well as 230 aircraft, a defense official told the Wall Street Journal.

It will also be the first time six F-22 Raptors will visit South Korea, and it will focus on enemy infiltration and precision airstrikes, according to Yonhap news.

The drill will close out a heated 2017 where President Donald Trump and North Korean leader Kim Jong Un have exchanged vicious threats of destroying each other’s countries.

With the emphasis of stealth jets to the annual US-South Korea exercises, this drill will be unlike any others. The US typically invites international observers to its military drills, but North Korea simply has no way to track stealth jets.

In late September the US flew a B-1B bomber and a few F-15 fighter jets near North Korea, and Pyongyang never found out. In the past, the US has had to tell North Korea about B-1B flights, because North Korea can’t detect them on their own, a South Korean defense official told NK News at the time.

That’s why stealth jets in South Korea is a nightmare for North Korea.

North Korea sees US and South Korean military drills as preparation for an invasion to remove Kim. North Korea has specifically threatened to shoot down US B-1B bombers when they fly or where they rest at Andersen Air Force Base in Guam. Often, North Korea schedules its missile launches around the dates of US and South Korean drills in protest.

But North Korea has no chance of spotting, tracking, or shooting down stealth jets, and the commonly accepted role of stealth platforms as being “door kickers,” or weapons systems to start wars off, will only aggravate Pyongyang’s worst fears.

So a year of record-high tensions between the US and North Korea will end with practically invisible jets flying over the Korean Peninsula, and there is little that Kim Jong Un can do in response.

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