PC - WW2 era US invading Britain from Ireland?

Let's get the ASB parts out of the way and chalk it up to author fiat, since otherwise it ain't happening. Unmentionable Sea Mammal takes place and Germany conquers Britain. The government of Ireland rather understandably panics and asks the Americans if it could maybe send some nice young soldiers to help maintain order in Eire.

Is there any chance that, four or five years down the road, a successful US (plus Commonwealth/Free British and perhaps token Irish forces) invasion of the UK could be launched from Ireland? Would the Northwest (the coast north of Liverpool, perhaps) or (this seems less likely, but I'm far from an expert) the West Country be potential landing areas? Assume roughly equivalent circumstances to OTL - the Germans are still fighting in the East (forces lost to occupying Britain are balanced by not fighting the British in the Med, etc) and the Luftwaffe is outclassed by the Allied air forces. How does the Irish Sea compare to the Channel in terms of conditions?

What do the military men at home think?
 
If Germany can take England they can take the lot (Wales, Scotland and Northern Ireland) at that point no way does the republic get to invite US troops even if they wanted to and to send them means Ireland and USA declaring war on Germany.

So you are talking about invading Ireland from Iceland (or US) first, I think B36s with nukes are more likely or an invasion from the east USSR>Norway or from the south Western Africa > Spain > France... or just supporting the remains of the USSR. (in the unlikely event they are still in the game?)
 
What dates are we looking at? If OTL'ish USM, in 1940, so what, 1944-1945 time frame? I would guess that yes, such a thing would be possible, but the nature of the submarine war would need to be made clear, I would think. No interdiction of German U-boats from the UK, so guessing that this is going to make things a bit more difficult. Also, with all the UK aircraft industry in German hands, how is the balance of airpower going to be like OTL? And what about the effects of no bombardment of Germany by RAF Bomber command on anything like OTL levels.

More german production, and way less British/commonwealth air power, aircraft production, Not to mention no UK shipbuilding, and I cannot see where the balance of power is going to be much like OTL at all. Need more info.
 
The problem with any Ireland - Great Britain invasion is that the infrastructure in most of Ireland is awful (even today, never mind 70 years ago) and most of the west coast of Great Britain is terrible for landing forces on (and much it also has poor infrastructure).

If the US is willing to spend years and (the equivalent of) billions of dollars turning the Ards peninsular or the east coast of Eire into something approaching a 20th Century area then it's doable, if they try and go 'as is' (even today, for most of both NI and Eire) then I reckon they're risking a major failure unless they can capture Liverpool, Bristol or Glasgow docks undamaged and escort huge numbers of transport ships over the Atlantic.

There's a reason why we haven't been invaded for over 1,000 years and it's not all down to the Royal Navy and a hearty rendition of Hearts of Oak before breakfast. The British Isles, outside of a very limited number of places, is a terrible place to try and land an opposed army.
 
I once speculated on this, envisioning an Ireland that is until now neutral in Germany's favor (possibly after being allowed to retake Northern Ireland). Mostly, I considered how they'd get the Irish government to go along. The deal was this: if the Irish help, they can keep Ulster. If they don't, then the US will invade Ireland, return it to British rule, and enforce Prohibition on Ireland.
 

Deleted member 94680

There's nowhere on the west coast of England suitable for that kind of landing analogous to Normandy. Even less so if the nazis have a half decent defensive force in the British isles.

As pointed out, it'd be a nightmare getting the American forces to Ireland in the first place. It'd be an opposed crossing of the Atlantic with attacks by the U-boats all the way. Maybe even with added RN vessels turned over to the Kriegsmarine post invasion?

With even their miserable military intelligence the nazis are going to figure out what an American landing in Ireland means.
 
Fiddlesticks! I figured it would be too high a mountain to climb. Thanks for the replies, everyone.
 
To expand on what others have said, if the Americans could get control of the Irish Sea, an Invasion of the Isle of Man and Anglesey might be quite annoying, while at a later stage Isle of Wight, Scilly, Shetland, Orkney, Outer Hebrides and some of the Inner Hebrides is possible. Some of these places might make good Naval bases and Air bases.
 

Deleted member 94680

To expand on what others have said, if the Americans could get control of the Irish Sea, an Invasion of the Isle of Man and Anglesey might be quite annoying, while at a later stage Isle of Wight, Scilly, Shetland, Orkney, Outer Hebrides and some of the Inner Hebrides is possible. Some of these places might make good Naval bases and Air bases.

Suicide to attempt unless the US has complete Air and Sea superiority. If they have that, why not go straight for the British Isles?
 

Delta Force

Banned
Let's get the ASB parts out of the way and chalk it up to author fiat, since otherwise it ain't happening. Unmentionable Sea Mammal takes place and Germany conquers Britain. The government of Ireland rather understandably panics and asks the Americans if it could maybe send some nice young soldiers to help maintain order in Eire.

Is there any chance that, four or five years down the road, a successful US (plus Commonwealth/Free British and perhaps token Irish forces) invasion of the UK could be launched from Ireland? Would the Northwest (the coast north of Liverpool, perhaps) or (this seems less likely, but I'm far from an expert) the West Country be potential landing areas? Assume roughly equivalent circumstances to OTL - the Germans are still fighting in the East (forces lost to occupying Britain are balanced by not fighting the British in the Med, etc) and the Luftwaffe is outclassed by the Allied air forces. How does the Irish Sea compare to the Channel in terms of conditions?

What do the military men at home think?

Wouldn't there be German occupation forces in Northern Ireland, unless they give it to Ireland for some reason? Even if the Germans aren't in Ireland, it's not very far away, and the Germans could probably subdue Ireland militarily in a few days and carry out operations against American landing forces in and around the island. Ireland doesn't have a very strong military and any offensive operation directed against it from the United Kingdom (British or German) is an over-match akin to the Iraqi invasion of Kuwait.
 

Deleted member 94680

However if they did that they would have Nazi bases to worry about

Didn't stop Overlord and France was full of nazi bases. They did, however, have air and sea superiority. That's what I was implying.
 
If Germany can take England they can take the lot (Wales, Scotland and Northern Ireland) at that point no way does the republic get to invite US troops even if they wanted to and to send them means Ireland and USA declaring war on Germany.

So you are talking about invading Ireland from Iceland (or US) first, I think B36s with nukes are more likely or an invasion from the east USSR>Norway or from the south Western Africa > Spain > France... or just supporting the remains of the USSR. (in the unlikely event they are still in the game?)

Well I am going to assume that Hitler still invades the Soviet Union

I would agree that if England fell and was occupied, not just capitulated and declared an cease fire. it would be easier to just fight from Soviet Russia as the USA is concentrating its fighting there against japan anyways.

One of the other issues to think about is how the occupation would go. The Germans respected the British quite a bit. While the Nazi's could control what takes place at home, and may even get some support by the local populations ( france as an example ), forces outside of their control would obviously continue the fight.


strange how the Empire would have to come and rescue their masters. this in turn might create a more equal commonwealth or make for a much easier decolonization process after the war.

also note: if England fell then assume the following: Sweden, Turkey, Spain, Portugal join the axis. Portugal might be forced to join.
Greenland and Iceland would become US possessions.

You could also see a more aggressive approach against the Japanese in China from allied forces, with pushes from India and SE Asia as well as from the Russian North.

US supplies would roll into Siberia.

at the wars end, Vladivostok would be quite a large city, you would also see the Tran-Siberian rail network expanded as well.

I would also expect a deal to be reached in regards to the Chinese Civil War to then focus a united Chinese response for the war.

Axis forces really can't touch continental United States or Deep into the soviet Union.
it would be a tough slog
 
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One of the few things that TFSmith121 and I ever agreed on was that a Trans-Atlantic Invasion on the scale of Overlord or Downfall, by the US simply wasn't logistically possible.

Which says a lot.
 
Another point to consider is that OTL the Irish position was if the Sea Mammal happened then they would enter the War on the side of the UK, with senior level military and civil service connections having discussed/planned it, so if the UK had fallen most likely the Free State would have been next.
 
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