U.S. Flies Bombers Over South Korea In Show Of Force To North Korea

Days after North Korea conducted its most powerful nuclear test yet, two U.S. bombers flew over South Korea in a display of force — a warning to Pyongyang and reassurance to Seoul.

"U.S. and South Korean fighter jets escorted the bombers in their low-altitude flight over South Korea's Osan Air Base ... about an hour from the border between North and South Korea," NPR's Elise Hu reports. She says the supersonic B-1B Lancers are based in Guam.

On Friday morning local time, North Korea conducted its fifth nuclear test — the second such test this year. South Korea's Joint Chiefs of Staff estimated it was Korea's largest-ever nuclear test, Elise reports. The isolated nation has also conducted several other missile and rocket tests within the past year, at what Elise calls an "unprecedented rate."

The tests have prompted international condemnation — again, and with little apparent consequence. Strengthened sanctions on Pyongyang haven't discouraged Kim Jong Un from building up a nuclear program. In fact, as Elise reported last week, international censure and sanctions "only seem to have strengthened" Kim's resolve.

North Korea's worried neighbors, South Korea and Japan, have been calling for a stronger response, Elise says.

"Some factions in Seoul have renewed calls for a nuclear force in South Korea — which currently does not have nuclear weapons," Elise says.

Instead, Seoul relies on the U.S. "nuclear umbrella."

The Associated Press notes that flyovers by U.S. bombers are "fairly common" when tensions flare up on the Korean peninsula. Videos of such flyovers appear in North Korean propaganda as evidence of U.S. hostility, the AP notes.

The wire service has more on the implications of North Korea's most recent nuclear test:

"Nuclear expert Siegfried Hecker, who has regularly visited the North's nuclear facilities, estimates that the North may have enough nuclear fuel for about 20 bombs by the end of 2016 and the ability to add about seven new bombs a year.

" 'Left unchecked, Pyongyang will likely develop the capability to reach the continental United States with a nuclear tipped missile in a decade or so,' [Hecker] wrote on the North Korea-focused website 38 North. He said that more troubling was the recent test successes may give Pyongyang a false sense of confidence.

"Six-nation diplomatic talks aimed at ridding the North of its bombs have been stalled since the last round of meetings in late 2008."