During which time shelter is required which is why the war tunels are possibly pretty useful.
I agree that there is little or no chance that the Channel Islands would receive a hit other than by unfortunate undershoot or overshoot from another target. Although the proximity of several reasonably high profile targets on both the southern UK coast and northern French coast do present a certain amount of risk to the islands. An airburst a mile or so off the coast would be somewhat unpleaasant.
Just staying inside your house is good enough to be honest. All you need to do is keep the dust off you/not breath it in. You don't need big reinforced concrete bunkers for that.
On proximity, have you looked at the maps and distances involved? Far more of England is within a short distance of a major target from the list given than any of the islands (bar Alderney) really. The winds aren't blowing in the direction of the islands, and even if they were, the calculator images I put up in my post for a 1Mt ground burst, hardly show any fallout reaching the islands even in the worst case scenario that the winds are pointing in the right direction.
At the worst it looks like that area of France is going to get off lightly with fallout. Unpleasant yes, but a darn sight better off than ~60% of the UK by those other maps!
Furthermore the weather maps are important because they are critical to the amount of fallout. I can look up fairly limited weather reports by searching Google that tells me that it was raining on the date given in parts of France. This will certainly reduce fallout spread, but what it will have done is concentrate fallout in the rivers, streams lakes and ponds in the immediate aftermath. A lot of fresh water fish and people are going to die from ingesting that water where it was raining (Caen, Normandy, West coast of France, Bordeaux: I presume from pressure chart and the few weather stations in France I cared to sample from the almanac I found).
A 'miss' is highly unlikely to effect any of the islands, compare just a couple hundred km square to the 10,000 or so km square on any of those maps of the region and you get an idea of how for a random miss the odds of hitting a location that could effect the islands is small. In fact that’s the same with any argument for any 'unfortunate miss' on a target. Nukes may have massive blast radius compared to normal bombs, but they are still really 'drops in the ocean' compared to the scales of nations.
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Now the whole "return to feudalism" thing is a lot of rubbish...
That's not what I said though was it
, so don't 'quote me' as if it was.
I concur that your not going to see feudalism, but I can quickly see a form of 'Balkanisation' or 'devolution to local governance' occurring. This is what I meant by 'kingdom of fiefdoms' and that where you've got strong centres of power, your going to have better recovery because they are already organised to deal with it. In particular you're going to have the island governments seeking out the situation in France and getting involved there because the islands themselves cannot just sit there on their own, they need to import some foodstuffs and nearly all manufactured goods. Thus making a proactive, outward looking situation the only sane option for a post war government. This means making contact with the French 'controllers' and local populaces. I apologise if I wasn't clear on what I meant.
I agree that in terms of an agricultural 'bread basket' the whole Brittany/West Normandie area is going to be very important to the recovery, your probs right about the bacon! But I don't know what dominated French agriculture back then in this region.
However I do believe your going to see more than the channel islands being a simple 'way point' after all they have got what few other places in Europe will have at this time; a complete continuity of government and modern infrastructure having suffered no direct attack.
Unless of course Mac decides that they did cop a bomb or two, but he hasn't mentioned it so far, and through the sources I've included (which is more for the arguments against it) nearby targets in France should have minimal effect to the islands anyway. He'll have to decide in the end how this all resolves, my main point was to draw attention to the fact that the Channel Islands do exist, and that for all intensive purposes might actually have a substantial effect on the recovery process of the regions.