On May 3, the United States tested its Minuteman III intercontinental ballistic missile for the second time in recent weeks. As in the April 26 test, the unarmed missile was launched from Vandenberg Air Force Base in California and flew 4,200 miles, landing near the Marshall Islands. The Minuteman III is the only land-based missile in the U.S. nuclear triad, and the United States tests them regularly for accuracy and reliability.