(USA TODAY) -- The United States military said Thursday that it flew in two nuclear-capable B-2 bombers to take part in military drills with South Korea after days of bombastic threats from North Korea to turn the U.S. ally into a "sea of fire."
U.S. Strategic Command said the B-2s made the 6,500-mile trip from an air base in Missouri to the Korean Peninsula to show how the United States can conduct long-range precision strikes quickly.
The massive bombers dropped dummy munitions on a South Korean island bombing range and returned home in a single, continuous mission. Known as "Stealth Bombers," they are designed to fly undetected by Soviet-era radar.
"The B-2 is designed to penetrate Soviet airspace and if necessary could penetrate North Korea at a time of war," said Bruce Klingner, a senior research fellow for Northeast Asia at The Heritage Foundation and a former Korea Branch chief for the CIA. "Given North Korea's increasing threats against South Korea and the United States, including threats of nuclear annhilation, this is meant to deter and send a message that the United States is prepared to respond if things get hot."
The flight also signals to U.S. ally South Korea that the USA intends to fulfill its treaty obligations to defend it if necessary, Klingner said.
"The United States is steadfast in its alliance commitment to the defense of the Republic of Korea, to deterring aggression, and to ensuring peace and stability in the region," stated United States Forces Korea, which oversees all U.S. forces based in South Korea.
North Korea has already threatened nuclear strikes on Washington and Seoul in recent weeks. It said Wednesday there was no need for communication in a situation "where a war may break out at any moment." Earlier this month, it announced that it considers void the armistice that ended the Korean War in 1953.
The new government in Seoul, led by President Park Geun Hye, has said it will not tolerate any attacks from the North, which has launched assaults against previous governments.
Park has said she wants to re-engage North Korea, stressing the need for greater trust, but that Pyongyang will "pay the price" for any provocation. Last week she approved a shipment of anti-tuberculosis medicine to the North.
North Korea is a reclusive Communist dictatorship led by Kim Jong Un, who took power after his father's death in December 2011. In 2010, North Korea sank the South Korean naval corvette Cheonan south of the maritime boundary, killing 46 sailors. That year it also attacked Yeonpyeong Island with artillery, killing four South Koreans and destroying 70 homes and buildings.
This month the North Korea Foreign Ministry announced it may attack the United States with nuclear missiles it claims can reach Hawaii and Guam, where the U.S. military has a base. The United States and the United Nations have approved sanctions against the North to get it to end its nuclear program, which is an violation of international agreements signed by the North.
At the land border Thursday between the two countries, South Korean soldiers stood at one side of a gate as trucks rumbled through without incident carrying large pipes and containers to Kaesong, an industrial zone in North Korea. Since 2004, the Kaesong factories have operated with South Korean money and know-how; North Korean factory workers are managed by South Koreans.
North Korea in recent weeks cut other phone and fax hotlines with South Korea's Red Cross and with the American-led U.N. Command at the border. Three other hotlines used to exchange information about air traffic were still operating normally Thursday, according to South Korea's Air Traffic Center.