Is tritium a showstopper?

Tritium is radioactive and must be handled carefully, but it is a well-understood, low-energy emitter managed with low inventories (6.47 kg startup), permeation barriers and monitoring. Crucially, the breeder breeds its own (4.0 kg/yr/yr at TBR 1.8), so supply is a feature, not a bottleneck.

Kronos names tritium handling as a licensing-relevant gate rather than waving it away.