Solid-fuel reactors are atomic pressure cookers, with the constant danger of high-pressure ruptures, meltdowns, and the forceful ejection of radioactive material into the environment.

FORBES: UK Parliament Group to Study Thorium Reactors

Sea water is being pumped into the reactors by special high pressure fire extinguisher hoses to prevent a nuclear meltdown.

FORBES: Radiation Levels Near Fukushima Up, Tokyo Unchanged, Says IAEA

Cooling systems to the reactors were knocked out, fuel rods overheated, and attempts to release pressure in the chambers led to explosions in the buildings housing the reactors.

BBC: Japan nuclear: Tepco halts Fukushima cooling plan

The designers of the reactors at Fukushima-Daiichi had anticipated situations where pressure was rising in the core.

FORBES: Explainer: What Caused The Incident At Fukushima-Daiichi

That is a very different situation than at Fukushima Daiichi, where the fuel in three reactors is thought to have burned holes in their immediately surrounding pressure vessels, and in one case to have fallen all the way through to the bottom of the outer containment vessel.

WSJ: Japan to Take 40 Years to Dismantle Fukushima Nuclear Plant

Mr Noda has been under pressure from anti-nuclear activists since he ordered the restart of two nuclear reactors in June.

BBC: Japan marks Hiroshima bombing amid anti-nuclear calls