This military base is training to shoot down a North Korean nuclear missile

See America's last line of defense against nukes
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Fort Greely, Alaska (CNN)"Impact location is Los Angeles," the major says. "We are engaging the threat at this time."

The crew inside Fort Greely homes in on the incoming intercontinental ballistic missile, launched from enemy territory and heading straight for California.
This is, thankfully, a drill, declassified so CNN can see a scrubbed-down version of the practice runs that take place repeatedly at Fort Greely, home to America's last resort against a launched ICBM.
"We have engaged the threat to Los Angeles with 2 GBI's," calls out the major, who could not be named for security reasons.
    He and the National Guard soldiers of the 49th Missile Defense Battalion are hunkered down in the Fire Direction Center -- so named because, among other tasks, it is responsible for the tactical-level execution of the interceptors. The GBIs, or ground-based interceptors, are being launched from Fort Greely and from Vandenberg Air Force Base in California.
    National Guard soldiers participate in a drill inside the Fire Direction Center. The name tag of one of the officers pictured here has been obscured for security reasons.
    The drill ends in success. "The threat to Los Angeles has been intercepted and destroyed," the major calls out.
    CNN was allowed in for a rare on-the-ground visit to see the only protection America has against an incoming North Korean ICBM: the Missile Defense Complex housed at Fort Greely.
    A ground-based interceptor missile stored at Fort Greely, Alaska
    Located in a desolate section of Alaska's wilderness 150 miles outside of Fairbanks, missile silos lie buried deep in the ground. Thirty-eight missiles, hidden under clamshell openings, point to the sky and sit ready for launch. An additional six missiles are slated to be in place at Fort Greely by the end of the year.
    Alaska National Guard soldiers accompanied CNN into one of the missile silos to see one of the white interceptors. We were warned that, at any moment, an alarm could go off and we would have to drop all our camera gear and evacuate before the interceptors launch.
    Fort Greely is on the front lines of protecting the United States from a possible threat by North Korea.
    "The kill vehicle is right there, towards the top," said Lt. Col. Orlando Ortega, commander of the 49th Missile Defense Battalion, pointing out the key technology that sits toward the top of the missile. The "kill vehicle," technically known as the Exoatmospheric Kill Vehicle, or EKV, is designed to slam into the incoming missile and destroy it.
    "We train to shoot a bullet at a bullet, and destroy it so it doesn't destroy us," the National Guard major said. "North Korea is really becoming more aggressive in their testing and in their rhetoric. What that does is, it just makes it more real for us."
    On April 16, 2017, North Korea parades ballistic missiles  through Kim Il Sung Square during a  parade in Pyongyang.
    "Now I've got a leader of a foreign country who says I'm going to take my missile and I'm going to kill your citizens with it," he said.
    All the soldiers CNN spoke with expressed extreme confidence in the interceptors' ability to take down an incoming ICBM, despite a 60% success rate.
    Thirty-eight interceptor missiles lie under the frozen ground, pointed to the sky and ready for launch.
    According to data from the Missile Defense Agency, in 18 tests conducted, interceptors have struck their targets 10 times. All those tests were controlled launches.
    "Just because we've had some failures doesn't mean we're not learning," said Sen. Dan Sullivan, R-Alaska. Sullivan said he believes the interceptors are still America's best shot as a last defense against North Korea. He's introduced a bill boosting the number of missiles to 72, increasing testing of the missiles and studying the possibility of increasing the number of interceptors to 100.
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    Sullivan readily admitted the missile defense program has a 60% success rate, but said the technology continues to improve with every test -- as shown by a successful ICBM intercept by the Missile Defense Agency in May. He also said the program, costing $40 billion so far, will see additional costs into the billions if his bill passes. Expensive, he said, but a necessary insurance policy in the face of Kim Jong Un's unpredictable and unstable behavior.
    Training has ramped up, the soldiers said, in the face of the increased activity from North Korea. They know they're the final line of defense and, if called, they cannot miss.
    For these soldiers, part of a remote and isolated team working in brutal weather that includes temperatures 40 below zero and little daylight in winter, it's a mission that's also deeply personal.
    "I think about my family. I think about my family in Georgia. Everyone does," said a young soldier, who identifies herself as a sensor operator; her name was also withheld for security reasons.
    One of 300 soldiers at Fort Greely who protect 300 million Americans.
    She is one of the many nameless soldiers who do a job few Americans ever see or understand. "We perform a mission for them," she said. "We do this job absolutely 100% to defend them."
    The members of the 49th Missile Defense Battalion refer to themselves as the 300 soldiers who protect 300 million Americans in all 50 states.
    "It's no longer a matter of if, but when North Korea is going to have the capacity to have an intercontinental nuclear missile," Sullivan said. "I think doing nothing in the face of this threat is not an acceptable option, and I think most Americans would agree with me on that."