(ABC News) In the remote Alaska wilderness, some 3,800 miles from Pyongyang, North Korea, the United States’ last line of defense against a nuclear warhead from North Korea or Iran stands ready to attack.

Fort Greely, Alaska, a World War II-era Army base that was reopened in 2004, is America’s last chance to shoot down a missile from overseas that could be carrying a nuclear weapon. Its underground steel and concrete silos house 26 missile interceptors that have, in tests, a 50 percent success rate.

The 800-acre base is located some 100 miles southeast of Fairbanks, in the looming shadow of Denali. It is one of only two missile defense complexes in the country. The other, Vandenberg Air Force Base in California, houses four interceptors that are used for testing and “backup,” according to defense officials.

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