The U.S. is prepared to launch a preemptive strike with conventional weapons against North Korea should officials become convinced that North Korea is about to follow through with a nuclear weapons test, multiple senior U.S. intelligence officials told NBC News.
North Korea has warned that a "big event" is near, and U.S. officials say signs point to a nuclear test that could come as early as this weekend.
The intelligence officials told NBC News that the U.S. has positioned two destroyers capable of shooting Tomahawk cruise missiles in the region, one just 300 miles from the North Korean nuclear test site.
American heavy bombers are also positioned in Guam to attack North Korea should it be necessary, and earlier this week, the Pentagon announced that the USS Carl Vinson aircraft carrier strike group was being diverted to the area.
The danger of such an attack by the U.S. is that it could provoke the volatile and unpredictable North Korean regime to launch its own blistering attack on its southern neighbor.
"The leadership in North Korea has shown absolutely no sign or interest in diplomacy or dialogue with any of the countries involved in this issue," Victor Cha, the Korea Chair at the Center for Strategic and International Studies told NBC News Thursday.
On Wednesday, North Korea said it would "hit the U.S. first" with a nuclear weapon should there be any signs of U.S. strikes.
On Thursday, North Korea warned of a "merciless retaliatory strike" should the U.S. take any action.
"By relentlessly bringing in a number of strategic nuclear assets to the Korean peninsula, the US is gravely threatening the peace and safety and driving the situation to the brink of a nuclear war," said North Korea's statement.
North Korea is not believed to have a deliverable long-range nuclear weapon, according to U.S. experts, nor does it yet possess an intercontinental missile.
South Korea's top diplomat said today that the U.S. would consult with Seoul before taking any serious measures. "U.S. officials, mindful of such concerns here, repeatedly reaffirmed that (the U.S.) will closely discuss with South Korea its North Korea-related measures," foreign minister Yun Byung told a special parliamentary meeting. "In fact, the U.S. is working to reassure us that it will not, just in case that we might hold such concerns."
"Two things are coming together this weekend," said retired Adm. James Stavridis, former commander of NATO and an NBC analyst. "One is the distinct possibility of a sixth North Korean nuclear weapons detonation and the other is an American carrier strike group, a great deal of firepower headed right at the Korean Peninsula."
The U.S. is aware that simply preparing an attack, even if it will only be launched if there is an "imminent" North Korean action, increases the danger of provoking a large conflict, multiple sources told NBC News.
"It's high stakes," a senior intelligence official directly involved in the planning told NBC News. "We are trying to communicate our level of concern and the existence of many military options to dissuade the North first."
"It's a feat that we've never achieved before but there is a new sense of resolve here," the official said, referring to the White House.
Implementation of the preemptive U.S. plans, according to multiple U.S. officials, depends centrally on consent of the South Korean government. The sources stress that Seoul has got to be persuaded that action is worth the risk, as there is universal concern that any military move might provoke a North Korean attack, even a conventional attack across the DMZ.
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