SEOUL -- South Korea has reached an agreement with the United States that lets Seoul more than double the range of its ballistic missiles to counter what it considers to be a growing threat from the North.
The revised agreement, which also tries to address Washington's worries of a regional arms race, increases the payload the ballistic missiles can carry and allows South Korea to develop and deploy more powerful unmanned aerial vehicles, or drones, that can carry more reconnaissance gear and weapons.
Under the revised guidelines, South Korea can deploy ballistic missiles with a range of up to 800 kilometers, or about 500 miles, enough to reach any target in North Korea but not enough to be considered a threat to China or Japan, as long as its payload does not exceed 500 kilograms, or 1,100 pounds. It can also load warheads weighing up to 2 tons on ballistic missiles with shorter ranges.
Until now, South Korea has been barred from deploying ballistic missiles with a range of more than 300 kilometers, or 187 miles, and a payload of more than 500 kilograms -- a capacity Korean officials believed was not enough to protect their country from North Korea's rapidly expanding nuclear and missile capabilities. The South was also banned from deploying drones that can carry more than 500 kilograms of weapons or equipment.
The new agreement allows South Korea to deploy drones that can carry up to 2.5 tons of equipment and weapons. Drones have emerged as a powerful weapon in modern warfare. They carry no human pilot on board and can be configured to fly higher than most conventional warplanes, making them harder to shoot down, according to military experts. South Korea began deploying low-flying reconnaissance drones in 2002.
"The biggest objective for the revision is to prevent North Korea's military provocations," said Chun Yung-woo, the chief national security adviser for President Lee Myung-bak.
With an ability to deploy longer-range missiles or shorter-range missiles with heavier payloads, South Korea can significantly increase its deterrence capabilities, Shin Won-shik, a senior policy-maker at the Defense Ministry, said during a media briefing.
North Korea has already deployed a number of missiles, including some capable of hitting the American territory of Guam in addition to South Korea and Japan, Washington's two main allies in Asia. In April, North Korea launched its Unha-3 rocket. Although the long-range rocket failed to put a satellite into orbit, the United States and its allies condemned the launching as a cover for developing intercontinental ballistic missiles.
The so-called missile guidelines, required by Washington in 1979 because of its concern over a regional arms race and revised only once, 11 years ago, had become a major grievance among South Koreans. Officials blamed the restriction for allowing their missile capability to fall behind that of North Korea's. Some key military installations in North Korea have been out of the range of South Korea's ballistic missiles.
Washington has vowed to defend South Korea, but Seoul's desire to beef up its missile capabilities gained support as North Korea expanded its nuclear weapons program, tested long-range missiles, and launched provocative military maneuvers including an artillery barrage on a South Korean border island in 2010.
Extending the range and payload of South Korean ballistic missiles has been a point of contention between Seoul and Washington. Another is South Korea's push to enrich uranium for fuel for its growing nuclear power industry. Washington is resisting the move, fearing that it would undermine efforts to slow the global proliferation of enrichment technology, as well as its attempt to persuade North Korea to abandon its nuclear weapons program.
Uranium, when highly enriched, can be used to fuel nuclear weapons. North Korea surprised Washington in 2010 by unveiling an advanced uranium-enrichment plant.
In the months leading up to Sunday's announcement, many in South Korea, including security analysts and conservative newspapers, have called on Washington to allow Seoul to develop more powerful missiles so their country could use the propulsion and fuel technology to bolster its nascent space program.
They called the missile restrictions a humiliating remnant of Washington's old patron-protégé relationship with Seoul that they said no longer befits today's South Korea.
The guidelines announced on Sunday "reconfirmed the limit in South Korea's diplomacy," said Lee Byong-chul, senior fellow at the Institute for Peace and Cooperation. "South Korean negotiators didn't secure enough of an opportunity for development in the face of their American counterparts' Fabian strategy of wearing them out."
South Korea first agreed to the missile guidelines in 1979 in return for American technological assistance in developing its first ballistic missiles. After Seoul's repeated requests for a revision, Washington agreed to extend the range from 180 kilometers to 300 kilometers in 2001, only after North Korea launched its Taepodong-1 missile over Japan in 1998.
American restrictions on ballistic missiles do not apply to South Korean cruise missiles.
In April, South Korea's Agency for Defense Development confirmed that it had developed and deployed a new cruise missile named Hyunmoo-3 that is capable of making a precision strike at a target anywhere in North Korea. Hyunmoo-3 is said to have a range of up to 1,500 kilometers.
But ballistic missiles fly faster and are thus harder to intercept, according to missile specialists.
This article originally appeared in The New York Times.