Putting aside the ongoing war of words between Beijing and Tokyo surrounding Japanese Prime Minister Sanae Takaichi’s statements on Taiwan last month, there is a simple question that needs answering. Can Japan’s Self-Defence Forces really afford to fight the People’s Liberation Army (PLA) without American military support?

Takaichi’s answer appears to be that Japan’s military must do so. The legislation approved by Japan’s Diet in September 2015 allowed the country to exercise its right of collective self-defence – albeit only to a limited degree – even if Japan is not directly attacked.

There are three conditions on acting on this right: if an attack against a foreign country with which Japan has close relations threatens Japan’s survival; if there is no other appropriate means to repel the attack and ensure Japan’s survival and protect its people; and that the use of force must be limited to the minimum extent necessary.

Taiwan is not a foreign country, of course. Even if a conflict did break out across the Taiwan Strait and a few stray bombs accidentally fell into the waters off Yonaguni, Japan’s westernmost inhabited island, how could that be interpreted as a threat to Japan’s survival?

The same year that Japan passed its self-defence legislation, a few artillery shells from Myanmar government forces landed in a village in Yunnan province, injuring five villagers. The issue was resolved quietly because the Chinese government saw it as an accident.

The only territorial dispute between Beijing and Tokyo is over the Diaoyu Islands, which Japan calls the Senkakus. Although both have coastguard ships sailing in the waters off the islands, the two militaries have maintained a kind of tacit agreement of not sending their naval vessels into the disputed waters.

If the prospect of China and Japan coming to blows over disputed territory is so unlikely, it would be ridiculous for them to start fighting over Taiwan. Even if they did, there is no way Japan could win in any scenario.

Plus, if Beijing saw Tokyo’s military involvement over Taiwan as a given, why wouldn’t the PLA launch a pre-emptive strike on Japanese forces? Takaichi is inviting the very conflict she says she wants to prevent by raising the possibility of Japanese intervention.

There are three layers of strategic ambiguity around the Taiwan issue, stemming from China, the United States and Washington’s Asian allies. Beijing sees peaceful reunification as the best outcome and believes time is on its side. This can be seen in Beijing still mentioning peace across the strait despite the Democratic Progressive Party holding the Taiwan presidency for two consecutive administrations.

US strategic ambiguities are twofold. The first is its “one-China policy”, which is slippery enough that it seems it can take any shape at any time. The other is its continued refusal to specify whether it would assist Taiwan militarily in the event of an attack by the PLA.

This approach is meant to deter Taiwan from declaring independence, while keeping open the possibility of US military intervention is meant to dissuade Beijing from launching an attack and reunifying through force.

Then there are the US allies in Asia. Japan is obliged to provide logistical support and bases in the event of a war. However, when Pentagon officials pressed Japan and Australia in July to clarify what role they would play if China and the US went to war over Taiwan, neither target would commit to a hypothetical military conflict in advance and said that any decision would have to be made by the government of the day.

This refusal to stake out a clear position is understandable as there is little reason for allies to commit themselves when the US itself maintains its strategic ambiguity.

These layers of strategic ambiguity from multiple parties create a chain reaction. As long as Beijing believes peaceful reunification is still possible, it is unlikely to resort to military force against Taiwan.

Short of that, there is no need for the US to give up its strategic ambiguity. And as long as the US maintains that strategic ambiguity, there is little point in Japan raising Taiwan as an issue.

During an interview with Japanese television in February 2022, then-Japanese prime minister Shinzo Abe called on the US to drop its strategic ambiguity regarding the defence of Taiwan.

Abe reiterated his oft-repeated notion that “a Taiwan contingency is a Japan contingency” and that the establishment of mainland Chinese air and sea superiority around Taiwan would affect Japan’s territorial waters. This is the tail wagging the dog.

In fact, as the importance of Taiwan recedes under a more isolationist US presidency, Washington might move in the opposite direction towards greater strategic clarity.

US President Donald Trump’s desire to reach a grand bargain with China on trade issues is a strong incentive not to support antagonising the mainland and being dragged into a war over Taiwan.

According to a report in The Wall Street Journal last week, Trump told Takaichi during a phone call to “temper” her tone on Taiwan. That call took place hours after Trump spoke to President Xi Jinping. Unsurprisingly, Japanese government officials denied the claims made in the report.

Takaichi’s statement on Taiwan was a political act, aimed at shoring up her standing with a domestic audience. It will not go down in history as a useful legacy. In a country where prime ministers often last less than a year in office, her remarks are merely ripples that will soon disappear.

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