I would like to focus on a single question, informed by what is happening around the world: “What kind of ecosystem can we actually build in Japan?” When we look at the movements of startups and investors, and at “demonstration stages” like France, Japan’s position is often described with words like “a bit behind” or “smaller in scale.” But from where I stand in the private sector, working with fusion, I increasingly feel something more positive: that “almost nothing has been fixed yet,” and there is still a large amount of white space that can be designed from here on.

Japan has accumulated expertise in plasma physics, accelerators, and superconducting technology at universities and public research institutions, and also has a broad industrial base in nuclear power, precision manufacturing, materials, and electronics. The real contest starts now: how do we re‑bundle these seemingly scattered assets under the single theme of “nuclear fusion”? I believe it is crucial not to set “building the reactor itself in Japan” as the only goal. Rather, the key is how many “components, processes, and services that can only be realized in Japan” we can create, while staying connected to global startups and to host countries like France. In the end, the question is whether Japanese companies and researchers can become truly indispensable players within the global fusion ecosystem.

From that perspective, what I should do as a VC is not merely “invest money in fusion startups.” I believe I need to go a step further and engage in designing the ecosystem as a whole: deciding “at which layers we want to see more founders,” and “which technologies and talent within existing companies we want to draw into the fusion side.” I picture the landscape as a continuum—materials, measurement, control, vacuum, thermal management, power systems, regulation and standardization—and I want to invest and support businesses with a clear hypothesis such as, “If we fill this piece, Japan’s fusion ecosystem will become significantly stronger.”

When we think about Japan’s fusion ecosystem, designing the time horizon is also indispensable. The commercialization of fusion is clearly not a project that ends in 10 or 20 years; it is at least a several‑decades‑long marathon. Within that, we must articulate, also from the private side, “what we will demonstrate in the next 10 years, and what we will launch as businesses in the following 10.” While staying in step with government strategies and regulatory discussions, it will be important to draw in advance a division of roles such as: “this stretch of the journey is where startups and VCs take the risk,” and “from this phase onward, we hand the baton to operating companies and infrastructure investors.”

Finally, I want to write a little about how I personally feel as I try to engage with this field. Fusion is undoubtedly “a bet on the scale of humanity,” and in both technical and financial terms, it is not a theme where anyone can lightly promise success. Even so, I still want to place myself in the middle of it, because I have a rather personal and selfish motivation: if this bet does pay off, I want to be able to say that there were people from Japan who played a real part in it. Startups, researchers, policymakers, investors—each takes risks in their own domain and gradually expands the stage. On the far side of that accumulation, I want to see how far a “Japan‑born fusion ecosystem” can grow, through the arc of my own career. I would like section 5 to serve as a kind of statement of resolve for that journey.