Fusion is not just which route ignites; route physics, fuel cycle, materials, heat extraction, maintenance, regulation, and economics must all work.
System targetCompare controlled-fusion routes that could become net-electric power plants, instead of treating single experiments, route concepts, and unvalidated commercial products as equivalent.
Production pathSeparate tokamak, stellarator, laser inertial, and secondary routes, then integrate confinement or driver hardware with fuel cycle, tritium-breeding blankets, heat extraction, neutron-tolerant materials, remote maintenance, safety licensing, and grid economics.
Constraint mechanismA route-physics breakthrough is not enough for a plant; if tritium breeding, blanket heat extraction, plasma-facing materials, remote maintenance, availability, safety regulation, or net-electric gain lags, the system remains experimental or low-availability.
Improvement pathThe current priority is plant-level shared-constraint validation: advance tritium/blanket/heat extraction, neutron materials, remote maintenance, and safety licensing while primary routes prove repeatable, maintainable, economic net-electric paths.
Industry-chain impactResearch should focus on superconducting magnets, high-power lasers or pulsed power, tritium and lithium blanket materials, plasma-facing materials, remote maintenance, vacuum/cryogenic systems, and power electronics because these layers set the resource need from experiment to plant.
Main risksNet-electric gain may not repeat, tritium closure may fail, materials lifetime may be too short, maintenance downtime may be too long, safety cases may remain unclear, build cost may lose to alternatives, or secondary routes may stay immature.
Evidence supportCurrent evidence and graph structure support reading primary routes, secondary routes, and shared plant constraints separately; shared constraints are decisive for commercial availability and plant feasibility.