Last week, North Korea announced that it would permanently turn its clocks back half an hour on Aug. 15 and create its own "Pyongyang time." In a typically bellicose state media announcement, North Korea said the move was timed to coincide with the 70th anniversary of the liberation of the Korean Peninsula from Japan, whose imperialist force had committed the "unpardonable crime" of depriving Korea of its rightful time zone.

Internationally, Pyongyang time has largely been met with bemusement. Given North Korea's isolation, its new time zone is of little consequence for most of the world and Pyongyang time is more or less an horological oddity. The reaction south of the 38th parallel, however, has gone far beyond rolled eyes.

“It is highly regrettable that the North unilaterally changed its time zone with no consultation with us,” South Korean President Park Geun-hye said Monday, according to Agence France-Presse. Her comments, made at a meeting with top government aides, suggested that South Korea viewed the new time zone as yet another affront to efforts at reconciliation between Seoul and Pyongyang.

"While not responding to our proposals for dialogue and cooperation, North Korea has separated our standard times," Park said. "This is a regression of our efforts for inter-Korean cooperation and a peaceful unification."

Park isn't the only South Korean government representative expressing disappointment. On Friday, Unification Ministry official Jeong Joon-Hee warned that the new time zone could cause short-term problems for South Korean workers in the Kaesong industrial park, a jointly run complex just outside the demilitarized zone that allows South Korean businesses to work with cheap North Korean labor.

Kaesong was opened in 2002 during a relatively hopeful time of economic cooperation between the two rivals, and it remains one of the few areas of shared understanding between Seoul and Pyongyang. The park was shut down in 2013 because of tension between the two nations but was reopened after five months. Although any issues surrounding Kaesong should be only temporary, Jeong also expressed concern about the broader message sent by the clock change. "In the longer term, there may be some fallout for efforts to unify standards and reduce differences between the two sides," Jeong told reporters.

The perception of a broader message behind the change is understandable. There is no international body that sets the world's time zones, and time zones are often changed for political reasons. North Korea may say that the time zone change is inspired by Japanese imperialism, but it also sends a message to South Korea, which abandoned the Japanese time zone in 1954 but reverted to it in 1964 in a bid to remain in sync with U.S. forces stationed in the country. It is also worth noting that North Korea's time zone shift brings it more in sync with China, its largest political and economic partner.

The timing of North Korea's announcement, however, may be the largest source of South Korea's frustration. Last week, two South Korean soldiers were seriously injured by mines in the southern part of the demilitarized zone, which is controlled by Seoul. After the U.S.-led U.N. Command blamed North Korea for the mines, South Korea on Monday restarted propaganda broadcasts into North Korea for the first time in 11 years.

The tragedy is, this could actually have been a moment for improving relations between North Korea and South Korea, both of which had hoped to celebrate the 70th anniversary of the Korean Peninsula's liberation from Japanese rule. A number of joint events, including a friendly football match and an exhibition of the Joseon kingdom's cultural heritage, had been planned to highlight a shared history of opposition to the Japanese empire. Now, the Korea Times reports, all planned events have been canceled.

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