TOKYO — The U.S. is calling on its allies to work together to protect ships from Iranian threats in the Strait of Hormuz. The U.K., Bahrain and Australia have already decided to join the coalition, while South Korea is considering taking part. The issue is likely to come up when world leaders meet at the U.N. General Assembly in late September.

Japanese Prime Minister Shinzo Abe has huddled with officials several times this summer to discuss pros and cons of joining the coalition, but has yet to make a final decision.

When the idea was first announced, I thought Japan should participate, as it relies on the Middle East for about 90% of its oil imports. That compares to 75% for South Korea, 64% for India and 44% for China.

Of the roughly 1,700 Japanese vessels that passed through the Strait of Hormuz last year, about 500 were tankers, according to the Japanese Shipowners’ Association.

In light of the recent tensions, U.S. President Donald Trump has urged Japan and China to defend their own vessels. Trump has a point: The U.S. says it is no longer the world’s policeman, and it has become less dependent on Middle Eastern crude oil as it increases its own production. Japan should also play a role as a U.S. ally.

But after talking with a number of officials and experts, I have come around to the idea that Japan would be better off not getting involved in the coalition so deeply, both in terms of its international contribution and in terms of ensuring the safety of Japanese ships. 

The primary reason for objecting to the coalition is that the U.S. government itself is divided over its purpose. There are three factions within the Trump administration when it comes to Iran policy: There are the “Iran hawks,” led by Secretary of State Mike Pompeo and John Bolton, the national security adviser. The hawks want to pressure Iran militarily to undermine the Iranian regime.

Another faction, led by the Pentagon, is primarily concerned about freedom of navigation. Its main focus is to safeguard vessels. This group is leery of provoking Iran militarily. 

The third faction sees the military coalition operating in and around the Persian Gulf as a bargaining chip in future negotiations with Tehran over its nuclear program. President Trump himself belongs to this camp.

These divisions make any potential coalition like people on a train who don’t know where they are headed. So what happens if Japan gets on board? With Iran hawks in the driver’s seat, the passengers could be taken to the brink of war. If, on the other hand, the nuclear deal-makers get their way, Japan could look foolish for having committed so much to the coalition. 

Japanese shipping companies fear that if Japan joins the coalition, it could be seen as an enemy by Iran, putting their ships in the crosshairs. The prime minister’s office appears to share those concerns.

“The situation in the Strait of Hormuz is not that serious at this point,” said Akira Omori, managing director of the Japan Shipowners’ Association, at a symposium hosted by the Japan Institute of International Affairs on Aug. 9.

I will never say that Japan should just wait and see. I think there are at least two things Japan should do, even if it does not join the coalition.

First, Japan should be prepared to protect its own vessels, on the assumption that tensions in the Strait of Hormuz will rise and the risk of Japanese vessels being attacked will increase.

Japan has sent Maritime Self-Defense Force warships and P3C patrol aircraft to the Gulf of Aden off Somalia as part of its anti-piracy efforts. If there is an incident, it would be rational to use these troops to defend Japanese vessels. In the event of maritime security operations taking place under the Self-Defense Force Act, Self-Defense personnel will also be allowed to use force to safeguard vessels.

Second, Japan should focus more on a dialogue with Iran. The outcome of the crisis in the Strait of Hormuz depends on whether the U.S.-Iran dispute over the nuclear issue can be resolved and tensions between the two eased.

In that sense, Japan’s biggest potential contribution is as a mediator between Washington and Tehran, capitalizing on its long-standing relationship with Iran. Joining the coalition could undermine Japan’s diplomatic efforts.

Trump also hopes Japan can act as a go-between for the U.S. and Iran, rather than joining the coalition. When Abe told Trump in late May about his plans to visit Iran the following month, Trump reportedly asked Abe to talk to them about the issue.

To persuade Iran, it is important for Abe to meet the country’s supreme leader, Ayatollah Ali Khamenei, in person. Abe is the only global leader to have met Khamenei recently, other than Russian President Vladimir Putin. Khamenei is ready to meet Abe again, according to a source.

Japan can put its diplomatic ties with Tehran ahead of joining the coalition, provided Abe can persuade Iranian leaders to adopt a more conciliatory stance.