Missing from the scene of an escalating dispute over Japan’s export restrictions against South Korea is the US role in easing tensions between its two key Asian allies.

Washington’s prolonged silence is in contrast with its interventions in previous discords between Seoul and Tokyo over historical issues.

US President Donald Trump’s administration has stayed out of the latest conflict, which spiked after Japan last week tightened regulations on exports of hi-tech materials to South Korea. The measure was taken in apparent retaliation for last October’s ruling by the Supreme Court here that ordered Japanese companies to compensate Koreans forced to work for them during Japan’s 1910-45 colonial rule of the peninsula.

Asked to comment on the discord between Seoul and Tokyo this week, a US State Department spokesperson made a vague statement that Washington believes “it is critical to ensure a strong and close relationship between the three countries.”

The Trump administration seems to be keeping what observers here described as a “strategic silence,” acquiescing to Japan’s retaliatory steps against South Korea.

Japanese Prime Minister Shinzo Abe’s government might have gained prior approval from the US before tightening export regulations on South Korea.

It is notable that Washington has been silent on Tokyo’s claim that materials shipped from Japan to South Korea, which could be used to produce the highly toxic VX and sarin gases, might have been routed to North Korea. Seoul officials have dismissed the claim as groundless, urging Tokyo to give substantial evidence.

In the past, the US administration has drawn a line on suspicions raised by other governments that seem to lack concrete grounds.

Washington’s stance may be seen as acquiescing Tokyo’s attempt to link its trade retaliation over a diplomatic issue to security concerns that stem from what it arbitrarily called Seoul’s lax implementation of international sanctions against Pyongyang.

As some experts indicate, the latest move might go beyond mere trade retaliation and could be seen as a warning from both Tokyo and Washington regarding Seoul’s stance, which they see as biased toward Pyongyang.

As some experts note, the US’ silence might also be due to practical economic considerations and Trump’s indifference to the value of alliances and multilateral mechanism.

A suspension of supplies of semiconductors and displays made by South Korean companies would have limited consequences for US tech firms. Rather, US chipmakers could benefit from it.

Trump has preferred to deal with foreign governments on a bilateral basis to maximize US national interests. It is certain that Abe has been more willing and adroit than South Korean President Moon Jae-in in responding to Trump’s approach.

The US government might also be more inclined to side with Japan, given it has unequivocally backed it in its trade and technology war with China while South Korea remains on the fence.

Seoul is planning to send senior diplomatic and economic officials to Washington for discussions with their counterparts in the coming week in pursuit of its role as a mediator.

Drawing attention is an upcoming trip to South Korea and Japan by the new top US diplomat for the region.

Assistant Secretary for East Asian and Pacific Affairs David Stilwell is scheduled to visit Seoul next week after meeting with Japanese government officials as part of his first trip to regional countries after assuming office last month.

It is hoped that his consultations with South Korean and Japanese officials will lead the US to play a mediating role and strengthen three-way coordination.

It would not be in the US interests to let Abe follow through with his aim to exclude South Korea from a new security framework being built in the Indo-Pacific region.

Seoul and Tokyo now seem prepared for a drawn-out standoff.

Moon on Wednesday urged Japan to stop heading toward a “dead end” in response to its rejection of his request to withdraw the export restrictions and hold negotiations.

A prolonged confrontation between South Korea and Japan would not be what the US needs ahead of the resumption of negotiations with North Korea on discarding the recalcitrant regime’s nuclear arsenal. It would also undermine Washington’s efforts to keep Beijing’s rising influence in the region in check.

The US should now step forward to help settle the discord between its key Asian allies.

The Moon administration needs to be more active in its security consultations with Tokyo and more flexible in handling historical issues to help build a momentum toward defusing the escalating row.