The latest meeting between Prime Minister Shinzo Abe and U.S. President Donald Trump was a sobering moment for Japan in many ways. In particular, last week’s summit has made one thing stunningly clear: It is not in a position to play a major role as the future of the Korean Peninsula is being determined by the United States, China and the two Koreas.

The developments since the stunning announcement on March 8 about the planned summit between Trump and North Korean leader Kim Jong Un — Kim’s surprise trip to Beijing for a meeting with Chinese President Xi Jinping; U.S. Secretary of State-designate Mike Pompeo’s visit to Pyongyang for direct talks with Kim; and North Korea’s announcement of its intention to suspend nuclear and missile tests as well as shutting down its nuclear facility — strongly suggest that the discussion both in the upcoming summit between Kim and South Korean President Moon Jae-in on Friday and the Trump-Kim summit will likely take place with an eye toward formally ending the Korean War when North Korea’s denuclearization is complete.

Not being a party to the existing cease-fire agreement for the Korean War, Japan is structurally handicapped to influence this process directly.

Japan has an additional disadvantage when it comes to dealing with North Korea. Since Japan’s defense posture has not moved beyond the parameter of being “exclusively defense-oriented” and therefore dependent on the U.S. for strike capabilities, North Korea does not need to fear Japan militarily. With Japan-North Korea bilateral economic transactions already at a bare minimum, another unilateral sanction imposed by Tokyo will have no noticeable impact on North Korea’s economy.

Furthermore, Japan has long held the position that it has no interest in normalizing its relationship with North Korea until the issues of Japanese abducted by North Korean agents in the 1970s and 1980s is resolved. In his meeting last Sunday with the families of the abductees, Abe reaffirmed that his government won’t consider this issue “resolved” until all the abductees return home. But without economic or military leverage of its own, Japan needs to rely on the leverage that other countries have with North Korea to take steps on the abduction problem. Simply put, Japan not only has very little leverage vis-a-vis North Korea on a bilateral basis, but essentially Tokyo needs Pyongyang more than the other way around to re-engage.

Finally, Japan faces challenges in enlisting support for its position from the countries that have major roles to play. Among the parties to the Korean War cease-fire (the U.S., China, North Korea and South Korea), the U.S. is the only country that Japan can count on to look out for Tokyo’s interest in its engagement with North Korea. While Japan does register its position with China and South Korea at every opportunity, Tokyo’s not-so-great diplomatic relationships with Beijing and Seoul raise the question on how effective such pleas are with them.

Even with the U.S., despite Trump’s personal commitment to “raise” the abduction issue and vow that his government would do “everything” it can to bring the abductees home, how strongly the U.S. will push North Korea when it shows signs of seriously discussing denuclearization along the line of its April 20 statement remains unclear. Indeed, one only has to look back on how the George W. Bush administration handled the balance between the abduction issue and other issues more directly relevant to addressing North Korea’s nuclear program.

The family of the abductees who visited Washington during the Bush administration received a warm welcome. In a 2003 visit, they met top congressional leaders, including the speaker of the House and both the Senate majority and minority leaders. In their 2006 trip, they met with Bush, who gave Sakie Yokota (mother of Megumi Yokota) a warm embrace, calling her “mom” and talked about his strong interest in seeing the issue resolved as soon as possible. And yet, during the six-party talk process, Japan was at times criticized by other participants (including the U.S.) for spoiling the progress at the talks by narrowly focusing on the abduction issue.

The dilemma for Tokyo is that, despite its limitation in influence over the engagement process with North Korea, Japan’s national security will be profoundly impacted by the results of the engagement, regardless of its result.

On one hand, any serious effort for North Korea’s denuclearization will neither be meaningful or sustainable without Japan’s assistance, financial and otherwise.

On the other hand, if the diplomatic effort breaks down, Japan will be immediately subject to a real risk of a second Korean War and its devastating fallout — both military and humanitarian — from it. Japan will be even worse off if the U.S. and North Korea emerge with an agreement that only targets North Korea’s nuclear weapon capability, as it will leave North Korea’s other conventional military capability that poses a threat to Japan, including its short- and medium-range ballistic missiles, unaddressed.

Given the circumstances, however, working with and through the U.S. remains Japan’s best bet if it wants to play a meaningful role in shaping not only the settlement of nuclear-related issues vis-a-vis North Korea but also the ultimate fate of the Korean Peninsula. To do so, however, Japan will need to open a policy discussion on highly politically sensitive issues.

Among such issues are: a possible redefinition of “the resolution” of the abduction issue; whether and how Japan can accept a massive influx of people who flee from South Korea to its shores (not only Japanese, Americans and other foreigners living there, but also South Koreans) if military action becomes imminent; whether Japan would be willing to provide not only financial but also technical assistance to North Korea as it proceeds with denuclearization, including training North Korean government officials on how to install enforceable export control system to prevent proliferation of nuclear weapon-related materials.

If the Abe administration can work through these sensitive issues and put together a proactive action item that it can present to the U.S. as it gears up for the Trump-Kim meeting — and then with China and South Korea as appropriate — Abe’s effort to look out for Japan’s interest in the rapidly moving developments on the Korean Peninsula will more likely to be successful.

Yuki Tatsumi is co-director of the East Asia Program at the Stimson Center in Washington. She is also a senior fellow at Canon Institute for Global Studies in Tokyo.