Korea has expanded its air defense identification zone to assert its sovereignty and maximize national interests in the face of China’s unilateral announcement of an expanded zone last month.

As expected, Korea’s new ADIZ encompasses Ieodo, a submerged rock some 150 kilometers off Marado, the nation’s southernmost island. China angered Korea by including the reef in its new perimeter, ignoring Korea’s jurisdiction over it.

The Seoul government also included in the new ADIZ part of Korea’s territory, including Marado and Hongdo, an island off the southern coast, which has been left excluded since the United States drew the old zone in 1951 in the middle of the Korean War.

The Ministry of National Defense says the expansion is in line with international aviation order and regulations as the new zone’s southern boundary matches Korea’s flight information region, a line drawn by the International Civil Aviation Organization to ensure the safe and efficient conduct of flights. The ministry has left the eastern and western boundaries unchanged.

The Korean government has every right to readjust its air defense zone to ensure its territorial integrity and protect its national interests. And Washington has suggested it would back Seoul’s move.

But the problem is that China and Japan have no intention of recognizing the readjustment. This means the Ieodo area is included in the ADIZs of the three East Asian neighbors, boosting the possibility of accidental military clashes among them.

Now, having proclaimed a new ADIZ, the Seoul government needs to start talks with China and Japan to address this problem and discuss readjustment of the three countries’ overlapping boundaries.

At the same time, Korea needs to beef up its air and naval capabilities to effectively manage and control the expanded ADIZ. In the first place, it needs to acquire aerial refueling tankers to extend the operation time and range of its fighter jets.

The air bases in Daegu and Gwangju are too far from Ieodo. F-15K strike fighters scrambling from these air bases can only operate over Ieodo for about 20 minutes. The operation time of KF-16 jets is even shorter ― just five minutes.

In-flight tankers can significantly extend the operation time of these fighter jets. So the government plans to purchase four aerial refueling tankers and will select the manufacturer next year. It needs to expedite the acquisition process.

A better solution is to expand the current airport on Jejudo Island and allow the military to use it. On the campaign trail, President Park Geun-hye promised to expand the airport infrastructure on the island to help it handle its ever-increasing flow of tourists.

It is also necessary to augment naval forces to enforce the new ADIZ. Currently Korea has only three state-of-the-art Aegis destroyers, not enough to create a squadron that can operate in the newly included air-defense zone south of Ieodo for an extended period.

To deal with this, the government has rightly decided to advance a plan to build three more Aegis destroyers. Last month, the military delayed the building plan, concluding that additional procurement of the ships was not that urgent.

Now, building a naval base on Jejudo Island has become all the more important. The base will allow the Navy to deploy ships to Ieodo in eight hours, less than half the time required for ships departing from its Busan base.