What would happen to the Republic should terrorists attack the Sellafield reprocessing plant? Probably nothing unless we were very unlucky, despite the doomsday scenarios circulating in the media.
Some commentators are talking about thousands of deaths here if a passenger jet were flown into the plant although how these deaths might occur is usually less well described. All this does is frighten further a nervous public, already jittery following the horrific events of September 11th.
For its part, the British government's timing in sanctioning the scale-up of Sellafield's new MOX (mixed oxide) nuclear fuel production plant so soon after New York could hardly be described as sensitive. It allowed Sellafield's opponents to link the plant with the events of September 11th and fan a presumption that an attack there would be equally devastating.
Unfortunately there are a lot more tempting targets than Sellafield. Any of the dozens of working UK nuclear reactors, particularly the aging Welsh reactors which are equally close to our coastline, could produce a more damaging terrorist result. Canary Wharf in London or the Houses of Parliament would also make better targets, offering television access that would duplicate the horrible coverage we endured when the Twin Towers died.
Yet the public and the Government here should aim vigorously for Sellafield's closure, not because it might be a terrorist target but because for us it breaks the fundamental precept of radiological protection. It does not pass the ALARA test, a measure that allows the UK government to support Sellafield's existence.
ALARA (As Low As Reasonably Achievable) is at the centre of nuclear safety. It says attempts to limit unwanted radiation exposure to the public should be tempered by any benefit the nuclear plant might bring.
Power plants might produce higher background radiation but they also deliver electricity. X-rays involve dangerous radiation but the benefits to the patient are undoubted.
Clearly, Sellafield passes the ALARA test for the UK government, given its decision to support the MOX plant. Equally clearly, it fails the test when applied here.
We face the risks of having such a plant 60 miles away, but gain no benefit from it. It provides no service to us yet we have to endure the pollution it pumps into the Irish Sea.
Its operator, British Nuclear Fuels Ltd (BNFL), constantly point to the falling radiation levels entering the Irish Sea from Sellafield, telling us the low levels will cause us no harm. The Radiological Protection Institute of Ireland has tested these claims and found that yes, it is true levels are dropping and within safe limits.
The same institute, however, also argues correctly that what is discharged is nonetheless radioactive pollution, which taints our shared sea and washes up against our coast.
BNFL's logic would dictate that you could put a few tablespoons of urine in a glass of water and drink it without harm, but would you really want to?
Nor should we on this island trust BNFL given its record of mishaps, accidents and incidents that include downright falsification. If nothing else BNFL has been consistent.
Windscale, as Sellafield used to be known, caused widespread pollution to the English countryside in 1957. In 1999 employees were caught falsifying safety data on fuel pellets shipped to Japan from the new MOX plant, which has now formally been opened for business. In between, there has been a litany of spills, discharges and leaks.
These are all good enough reasons for the Government and the voters it represents to go after Sellafield with everything at their disposal. Why should any of us have to put up with this when there is nothing in it for us? The new MOX plant will add yet more pollution to the burden already carried, despite remaining within limits set by those who might gain some benefit from Sellafield's presence in Cumbria.
Yet we should back away from the doomsday claims being made that there is some special additional risk from Sellafield post September 11th. Sellafield is one place where security at least has been considered, particularly because of decades of tricky Anglo-Irish relations. It has always considered itself a target for terrorist interest, although usually to those much closer to home.
Any risk to us posed by Sellafield, its various plants and the huge stores of highly radioactive liquid waste is predicated on radiation being able to reach us. There are too few places at Sellafield where major explosions linked with subsequent fires involving radioactive materials could release radioactivity high or wide enough to reach us in concentrated form. This would be necessary if significant harm is to be caused here.
There are a few large targets there, the old Windscale reactor, the MOX plant, the Magnox fuel reprocessing facility, the new THORP plant that separates uranium and plutonium from spent fuel and the high-level liquid storage tanks.
Windscale happened when carbon meant to moderate the nuclear reactor overheated, caught fire and burned out of control. It spewed radioactivity into the air which was carried on the wind to settle on nearby farms. This could be a target but the carbon would have to be reignited, difficult given the external shielding to this plant.
The reprocessing and fuel manufacturing plants use acids and other chemicals to treat and refine spent fuel. All these activities take place in heavily reinforced buildings and so a significant impact would be required to breech them.
If this happened and aviation fuel caught fire, then there is potential for radioactive material to be carried upwards. Large stores of exposed radioactive material would need to be available to make this a significant threat, as at Chernobyl where an explosion ripped open the core, exposing tonnes of fuel to the fire that followed.
Two of the worst possibilities are the rupture of the high-level liquid storage tanks or a fire involving plutonium.
The latter is a dangerous substance even at low levels. A strong fire has the potential to spread radioactivity, but it would have to be a large fire and the wind would have to be blowing in our direction to cause us harm.
Dick Ahlstrom is Science Editor of The Irish Times