SEOUL - Prime Minister Shinzo Abe may be looking for reassurance when he meets later this month with U.S. President Donald Trump, given that the Japanese leader has been left out of the rapidly progressing diplomatic talks to resolve the North Korean nuclear threat.

“Japan looks quite isolated and without really much of a role to play except perhaps to pay up once Trump finds a deal,” said Koichi Nakano, a political science professor with Sophia University in Tokyo.

Shared threat

Abe will visit with Trump at the president’s Mar-a-Lago golf club in Florida on April 17 and 18. This will be the third major summit between these two leaders. The White House, in a statement, said the summit would focus on North Korea sanctions, Trump’s upcoming meeting with North Korean leader Kim Jong Un, and on “fair and reciprocal” trade issues.

Abe has been perhaps the strongest supporter in Asia for Trump’s “Maximum Pressure” campaign to impose tough sanctions on North Korea, backed up with the threat of military action, to force the Kim government to halt its nuclear program.

Japan and South Korea are already within range of North Korean short and medium range missiles, and last year the North tested inter-continental ballistic missiles (ICBM) that flew over Japanese airspace as part of its accelerated efforts to develop a nuclear-armed ICBM capable of reaching the U.S. mainland.

FILE - People watch a TV news report on North Kore FILE - People watch a TV news report on North Korea, in Seoul, South Korea, Nov. 29, 2017. FILE - People watch a TV news report on North Korea, in Seoul, South Korea, Nov. 29, 2017.

But Abe was recently surprised by Trump’s decision to meet with the North Korea leader. Nor did he get any advance notice of Chinese President Xi Jinping’s recent meeting with Kim. The hardline Japanese leader has also seemed skeptical of South Korean President Moon Jae-in’s Olympic outreach to the North that has produced a pause in provocative missiles tests, an inter-Korean summit at the end of April and Kim’s commitment to engage in denuclearization talks with the United States.

The prime minister is expected to caution Trump not to get caught up in the diplomatic momentum that is fast moving toward a deal to ease sanctions in exchange for either a freeze or partial reduction in the North’s nuclear capabilities.

“I think that he will continue to urge the decision of the United States in the direction that the sanctions on North Korea should not be eased,” said Professor Hosaka Yuji, a Japan analyst at Sejong University in Seoul.

Abe may also bring up with Trump the issue of the hundreds of Japanese abductees that were kidnapped by North Korea in the 1970s and 1980s.

U.S. over-dependence

A partial denuclearization deal would continue to leave Japan exposed to a North Korean nuclear attack. The North’s improving ties with China and South Korea could also increase regional tensions for Tokyo over territorial disputes and disagreements over Japan’s World War II atrocities that had been kept in check by a unifying North Korean threat.

“The fact that Japan is neglected and that a peaceful framework of inter-Korean relations is being created without Japan does not help the current Japanese government at all,” said Hosaka.

U.S. President Donald Trump, left, meets with Prim U.S. President Donald Trump, left, meets with Prime Minister Shinzo Abe upon the arrival at the Kasumigaseki Country Club in Kawagoe, near Tokyo, Nov. 5, 2017. U.S. President Donald Trump, left, meets with Prime Minister Shinzo Abe upon the arrival at the Kasumigaseki Country Club in Kawagoe, near Tokyo, Nov. 5, 2017.

Abe has used the North Korean nuclear threat and the rising military power of China to build his political support, and justify his efforts to strengthen the Japanese military by altering the country’s pacifist constitution.

Japan’s relations with South Korea also continues to be strained over the “comfort women” controversy, regarding the thousands of Asian women who were forced into sex slavery by the Japanese army during the war. A 2015 agreement between Tokyo and Seoul has failed to settle the matter.

Abe’s total dependence on the U.S. alliance for security, and neglect in developing closer ties in the region, could leave Japan on the sidelines of regional diplomacy.

“By focusing so much on following the U.S. lead without developing Japan’s own diplomatic assets and relationships, Japan is now being found as not having much of a role to play,” said Nakano.

On trade, while Trump pulled out the Trans Pacific Partnership (TPP) free trade agreement with Japan and other Pacific nations, he initially voiced support for improving bilateral trade.

But recently the Trump administration included Japan in the list of countries that will have to pay 25 percent tariffs on steel and 10 percent charge on aluminum exports to the United States.

As a key U.S. security ally, Abe will likely seek a similar tariff exemption granted to South Korea.

Abe’s approval rating at home is also slipping due to corruption scandal involving allegations that he used his office to help friends and family.

Lee Yoon-jee in Seoul contributed to this report.