Seoul and Tokyo have been stepping up three-way security consultations with Washington ahead of U.S. President Barack Obama’s trip to Asia next week.

Senior defense officials from South Korea, the U.S. and Japan plan to hold a two-day meeting starting on Thursday in Washington. Last week, top nuclear envoys from the three nations met there to discuss coordination on North Korean issues, including its nuclear and missile programs and human rights abuses.

These discussions come on the heels of a trilateral summit Obama hosted to bring together South Korean President Park Geun-hye and Japanese Prime Minister Shinzo Abe on the sidelines of an international nuclear security conference in The Hague last month. Concerned about the growing antagonism between its two key Asian allies over historical and territorial disputes, the U.S. has sought to rebuild a united front with South Korea and Japan to cope with threats from North Korea and keep an increasingly assertive China in check.

Advice or pressure from the Obama administration seemed to be the driving force behind the talks between the two countries on Japan’s wartime sexual enslavement of Korean women, which were held in Seoul on Wednesday.

South Korea now considers it inevitable that it will have to manage relations with Japan through a dual approach, separating sensitive historical and territorial issues from security cooperation. What worries Seoul officials is that this position may provide Abe’s right-wing nationalist government with a pretext for disregarding calls for sincere efforts toward solving deep-rooted problems with South Korea. It was for this reason that President Park sought to limit the agenda for last month’s trilateral summit to North Korea’s threats and international nuclear safety.

It is regretful that Seoul’s concerns seem to have been validated by Tokyo’s recent moves. Japan angered South Korea early this month by issuing a foreign policy paper that renewed its claim to South Korea’s easternmost islets of Dokdo and approving school textbooks revised to promote its territorial stance.

On Saturday, Japan’s minister for internal affairs, Yoshitaka Shindo, visited a controversial war shrine in Tokyo, prompting the latest protest from Seoul. Bilateral ties between the two sides may be further strained if Japan continues to provoke South Korea over historical and territorial matters.

Washington has seemingly tried to dissuade Japan’s conservative leaders from making retrograde acts, especially after Abe paid homage last December to the Yasukuni Shrine, which honors 14 Class-A convicted war criminals along with millions of war dead. But the prevailing sentiment here is that the Obama administration has not been wholehearted in dealing with Tokyo’s whitewashing of its past wrongdoings.

It was an impressive scene when U.S. Defense Secretary Chuck Hagel faced off with his Chinese counterpart during his recent visit to Beijing, declaring that America will protect Japan and other Asian allies locked in territorial disputes with China, as laid out in U.S. treaty obligations. As noted by some commentators here, Japan might have halted its revisionist moves had Washington issued a warning with similar determination.

While Abe is putting all at stake to consolidate the U.S. alliance, South Korea is inevitably having to strengthen strategic cooperation with China, which is the only power with substantial leverage over North Korea and shares painful memories of Japan’s pre-1945 wartime atrocities. This situation may be leading the U.S. to weigh its alliances with South Korea and Japan differently.

But ultimately, it would better serve U.S. interests in the region to keep Japan in check over sensitive bilateral issues with South Korea, which would help consolidate the framework of trilateral cooperation and prevent Seoul from being further drawn into Beijing’s sphere of influence. In this context, South Koreans will closely watch what messages and signals Obama will give during his upcoming visits to Seoul and Tokyo, which precedes his trips to Malaysia and the Philippines.

For its part, Seoul needs to take active measures to further cement its alliance with Washington. It is sending mixed messages by belatedly ratifying an agreement on sharing the cost of stationing American troops here and remaining reluctant to join the U.S.-led regional missile defense shield, while requesting another delay in taking over wartime operational control from Washington.