A new critique of Atsuko Higashino's study of Japan, Ukraine and Central and Eastern Europe asks how we know what drove Tokyo's tougher line on Russia, and what evidence would settle it.
Japanese diplomacy toward Russia changed sharply between the 2014 occupation of Crimea and the 2022 full-scale invasion of Ukraine, and a new commentary argues that the well-documented story of that shift still has not explained why it happened. In an essay published in early October 2026, writer Friedrich Steinbrunner re-examines Atsuko Higashino’s paper, “Japan, Ukraine, and Central and Eastern Europe,” through the tools of international relations research.
Steinbrunner does not dispute Higashino’s account. Instead, he argues that her narrative already contains the raw material for a sharper question: what caused Tokyo to move from cautious sanctions in 2014 to robust, G7-coordinated pressure in 2022? His answer is a framework of hypotheses, rival explanations and conditions under which each explanation would fail.
What Higashino’s Paper Traces, From Eurasia Diplomacy to the G7 Hiroshima Summit
Higashino’s paper lays out Japan’s engagement with Ukraine and Central and Eastern Europe in chronological order. Steinbrunner describes it as accessible and easy to follow when read as a diplomatic history.
The milestones it covers include:
- 1990s: Japan’s “Eurasia Diplomacy.”
- Aso era: the “Arc of Freedom and Prosperity,” promoted while Taro Aso served as foreign minister.
- 2014: Russia’s occupation of Crimea and Japan’s first sanctions response.
- 2019: the Japan-EU Connectivity Partnership.
- 2022: Russia’s full-scale invasion of Ukraine.
- 2023 onward: Prime Minister Fumio Kishida’s visit to Kyiv, the G7 Hiroshima Summit, and President Volodymyr Zelenskyy’s meetings with leaders of invited countries.
According to Steinbrunner, the paper’s stated aim is to reflect on Japanese diplomacy since 2014 and to examine how it changed after the 2022 invasion.
Crimea 2014 Versus Invasion 2022: The Gap Steinbrunner Wants Explained
The core of the critique is a contrast Higashino herself documents. In 2014, Japan did impose sanctions on Russia over Crimea. Yet, as Higashino argues, the government of then-Prime Minister Shinzo Abe was careful to avoid a decisive breakdown in relations with Moscow.
By 2022, the response looked very different. Japan tightened sanctions, worked in step with its G7 partners and substantially expanded its support for Ukraine.
| Dimension | 2014 (Crimea) | 2022 (Full-scale invasion) |
|---|---|---|
| Sanctions on Russia | Imposed, but measured | Strengthened |
| Posture toward Moscow | Caution to avoid a definitive rupture | Clearly tougher |
| G7 coordination | Not emphasised in the account | Actively pursued |
| Support for Ukraine | Medical equipment aid from 2014 | Significantly expanded |
In academic terms, Steinbrunner calls this a “research puzzle”: a difference that demands an explanation, which can then be checked against theory and evidence. Leading journals in the field, he notes, reward that kind of puzzle-driven design over a list of events.
Why the Arc of Freedom and Prosperity Faded After Aso
Higashino offers several reasons why the Arc of Freedom and Prosperity never fully took root. The initiative leaned heavily on Aso’s personal drive, target groupings such as GUAM were institutionally fragile, and Eastern Europe was simply less urgent for Japan than it was for the European Union.
She also notes that the concept quickly disappeared from Japan’s diplomatic vocabulary once Aso left the foreign ministry. Steinbrunner cautions against reading that sequence as proof of cause. Over the same period, Japan changed government, the international environment shifted, the EU revised its own eastern policy and Tokyo’s priorities moved.
His point is a familiar one in research methods: one event following another is not the same as one event causing another.
Four Testable Hypotheses on Japanese Diplomacy Toward Russia
Steinbrunner argues that Higashino’s narrative already contains the variables needed for a model, even if they are not presented as one. He sets the strength of Japan’s Russia policy as the outcome and links it to four factors: security urgency, coordination with the United States and G7, the value Tokyo places on ties with Moscow, and how deeply a policy is institutionalised.
From those, he draws four hypotheses:
- Security urgency: the more pressing the security threat, the stronger Japan’s policy response.
- Allied pressure: the stronger the push for coordination with Washington and the G7, the firmer Japan’s stance on Russia.
- Value of Russia ties: the more Tokyo values its relationship with Moscow, the more restrained its sanctions.
- Institutionalisation: policies embedded in government bodies or international institutions outlast those that depend on a single politician.
A theory, he stresses, need not be mathematically complex. It must state what influences what, in which direction, and what evidence would disprove it.
“Not Found” Is Not “Did Not Exist”
Steinbrunner singles out one line in Higashino’s paper stating that there is no evidence certain explorations took place between Japan and Europe. Read casually, he says, that is unremarkable. Read as an evidentiary claim, it is a strong one.
He asks how far the search went: foreign ministry records, Diet proceedings, EU and NATO documents, and memoirs or interviews with diplomats. Without that scope spelled out, he suggests a more cautious wording, such as “cannot be confirmed within the public documents reviewed.” The absence of evidence, he reminds readers, is not evidence of absence.
From Kishida’s Kyiv Visit to Results: Activity, Output and Outcome
On Japan’s diplomacy from 2023, Steinbrunner separates three levels that are often blurred. Holding a summit is an activity. Issuing a joint statement is an output. A third country changing its policy as a result is an outcome.
He compares this to business: a hundred sales meetings do not guarantee a hundredfold rise in revenue. Anyone describing the “results” of the Hiroshima Summit or the Kyiv visit, he argues, should define what counts as a result.
Ukraine’s Medical Aid: From Delivery to Effectiveness
Higashino records that since 2014 Japan has sent Ukraine artificial lung ventilators, anaesthesia machines, emergency kits and other supplies, with medical equipment support of about 1.5 million dollars between 2014 and 2019.
Steinbrunner proposes a chain for judging such aid: requested, delivered, installed, used and effective. The questions that follow include whether equipment reached hospitals, how many units worked, how many patients benefited, whether parts and training were provided, and whether the gear stayed in use after the programme ended.
He is explicit that this is not a flaw in Higashino’s work, which was never designed to audit equipment performance. Her paper, he says, supplies material that others can turn into explanatory research.
China, the Alliance and Domestic Politics as Rival Explanations
To test the claim that the 2022 invasion transformed Japanese diplomacy, Steinbrunner recommends measuring the same factors on the same scale for both 2014 and 2022: security urgency, US and G7 pressure, the value of Russia ties, perceptions of China and domestic politics.
He also urges weighing competing explanations rather than settling on one. Ukraine may not have been the main driver. The shift could instead reflect concern about China, the Japan-US alliance, domestic changes around Japan’s National Security Strategy, a change of government or the G7 relationship.
Crucially, he sets out conditions that would undermine his own framework:
- Small real gap: if a common scale shows little difference between 2014 and 2022, the premise of a major shift must be revised.
- Russia ties overstated: if internal records show Tokyo in 2014 placed little weight on its Moscow relationship, that hypothesis weakens.
- China explains most: if the China factor alone accounts for the 2022 change, the Ukraine-centred explanation loses ground.
Mathematics, in his view, is not a machine for producing answers but an alarm that flags where evidence runs thin. A hidden third factor can drive two events at once, and when several causes produce one result, observers cannot always isolate each one’s share.
Why the Debate Over Tokyo’s Russia Policy Matters to Canadian Readers
General context: Canada, like Japan, is a G7 member, and the bloc’s coordinated response to Russia has been a recurring theme of allied diplomacy since 2022. Understanding what pushes a key partner toward or away from collective pressure on Moscow helps explain how durable that coordination may be. For a wider view of the hotspots shaping that agenda, see our roundup of global flashpoints Canadians should watch.
The essay’s broader lesson applies well beyond Tokyo. Policy narratives can be persuasive and still leave room for another explanation of the same facts. Steinbrunner’s conclusion is measured: the narrative is not wrong, but on its own it cannot pin down a single cause.
Frequently Asked Questions
Who wrote the original paper?
Atsuko Higashino wrote “Japan, Ukraine, and Central and Eastern Europe,” a diplomatic history of Japan’s relations with the region.
Does the critique say Higashino’s paper is wrong?
No. Steinbrunner says the paper is valuable and well-sourced, and that its material can be reshaped into explanatory research.
What is the main question raised?
Why Japan responded cautiously to Russia in 2014 but much more forcefully, and in coordination with the G7, in 2022.
When was the paper itself published?
Not specified in the commentary.
