U. S. Antimissile System Goes Live in South Korea - By CHOE SANG-HUNMAY 2, 2017 SEOUL, South Korea — An American missile-defense system deployed to counter growing threats from North Korea has gone into operation in South Korea, officials said on Tuesday. His statement was echoed by the South Korean Defense Ministry, whose representative, Moon Sang-gyun, said the battery “has acquired an initial capability to deal with North Korea’s nuclear and missile threat.” The announcement came ahead of a presidential election next week in South Korea that has been troubled by tension over the North’s nuclear weapons program and confusion about President Trump’s approach toward the Korean Peninsula. On Tuesday, South Korea’s main opposition party, the Democrats, called the government’s decision to accept the Thaad deployment “a total failure of diplomacy.” The American antimissile system — Terminal High Altitude Area Defense, known as Thaad — in South Korea has been deemed operational. The system “is operational and has the ability to intercept North Korean missiles” and defend South Korea, said Col. Robert Manning III, a spokesman with the United States military in Seoul, the South Korean capital.