South Korea is apparently facing growing pressure to join the U.S.-led global missile shield program, which could sour its ties with China and Russia.

Top Washington defense officials have talked of the need to step up bilateral missile cooperation as they are visiting Seoul for consultations over the planned transfer of wartime operational control and other pending security issues.

Washington has apparently wanted Seoul to join its multilayered missile defense program so that it can connect Japan and other regional partners under the network to counter missile threats from potential adversaries.

But Seoul has remained reluctant to participate in it as it could undermine its relations with Beijing, Pyongyang and others that the U.S. program could target in case of a contingency. Instead, it has been working on establishing a separate low-tier defense system to counter North Korean threats.

During his meeting with his South Korean counterpart Gen. Jung Seung-jo on Monday, U.S. Joint Chiefs of Staff Chairman Gen. Martin Dempsey said given the threat that North Korean ballistic missiles pose to the peninsula and the region, the Joint Integrated Missile Defense System has become more important.

“As the capabilities of the North have changed, we have to change right along with them,” he said during the Military Committee Meeting held in Seoul. “In fact, we try to change before they change.”

On his flight to Seoul last week, U.S. Defense Secretary Chuck Hagel also echoed his view, saying missile defense is one of the “big ones” that Seoul should focus on as it prepares for the transfer of wartime operational control.

“Obviously missile defense is a huge part of this. ISR ― intelligence surveillance, reconnaissance ― and command and control is a very big part of all this,” he told reporters on his flight to Seoul.

Hagel touched down in Seoul on Sunday for a four-day trip that would include his attendance at the allies’ annual Security Consultative Meeting, where Seoul’s request to reconsider the timing of the OPCON transfer currently slated for December 2015 is expected to top the agenda.

Some observers raised speculation that Washington officials could renew their calls for Seoul to join its missile defense network and link the issue to the consultations over the proposed delay in the OPCON handover.

Other analysts, however, said Washington might not push for it in consideration of the public sentiment against Seoul’s participation in the U.S. missile defense program.

Stressing that the allies have never had any official talks over whether to join the U.S. program, Seoul has been working on establishing its own missile shield specifically designed for Korean terrain features and security conditions.

The South’s envisioned program is called Korea Air and Missile Defense. Seoul’s lack of crucial intelligence assets for the KAMD including a military satellite is cited as the major problem for its development and operation.

Talk of the allies’ missile defense cooperation has emerged as Seoul has sought to enhance relations with Beijing, which observers say have been undermined due to the previous Lee Myung-bak government’s focus on the Korea-U.S. partnership.

Some analysts say the recent development in Seoul-Beijing relations may not be welcomed by Washington as the U.S. seeks to strengthen military and diplomatic ties with its core allies such as Japan and South Korea amid the rise of China.

For Washington, strengthening the trilateral security network of the alliances with Seoul and Tokyo is crucial.

But Seoul and Tokyo have been estranged as Japanese right-wing politicians refuse to fully atone for their country’s wartime atrocities and step up its territorial claim to Dokdo islets in the East Sea.

By Song Sang-ho (sshluck@heraldcorp.com)