unimog - I agree. My language was loose and I meant to say control rods. It's not clear that they are fully effective, and it seems as though there is still some percentage of operating power being developed by these reactors. So perhaps the control rods were damaged, or did not insert properly because the fuel rods were damaged?

And this comment in the news says it quite neatly ...

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Given the reported radiation levels, John Price, an Australian-based nuclear safety expert, said he saw few health risks for the general public so far. He was concerned for the workers, who he said were almost certainly working in full body suits and breathing through respirators. The workers at the forefront of the fight — a core team of about 180 — had been regularly rotated in and out of the danger zone to minimize their radiation exposure.

Price said he was surprised by how little information the Japanese were sharing.

"We don't know even the fundamentals of what's happening, what's wrong, what isn't working. We're all guessing," he said. "I would have thought they would put on a panel of experts every two hours."
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MY THOUGHTS: The surroundings of the reactor are too complex for a robot to operate, and I don't think that a military standoff weapon will solve the problem here. So the final solution seems to come down to someone volunteering to go in there to add coolant and try to seal off the radiation leakage. This could well involve loss of life for some of the power plant workers i.e. it is essentially a suicide mission. As I recall from Chernobyl, there was a very brave helicopter pilot who flew over that reactor and lowered a concrete plug - in order to seal it. He died within a few days from radiation poisoning. I wonder if we've got the same final outcome here??

other Pete