No matter what, an attempted German invasion would have been a complete disaster. Even IF the Luftwaffe had "won" the Battle of Britain.
The German Navy had been essentially wiped out in the invasion of Norway. They had really terrible, small landing craft. The Royal Navy was based at Scapa Flow and was a long flight for the LW. Once the invasion started, the RN would have been able to make it south and shoot up the landing craft...even if 90% of the RN was wiped out by the LW on the way the remaining 10% would have crushed the landing craft.
Sealion was really a half-assed joke. Britain was never in serious danger of invasion.
That's easy to say in hindsight. But that's not the point of alternate history fiction, or this sort of experimental documentary. There's much we can learn about the future by thinking about what happened in WWII, or what didn't happen and why.
All that is necessary for the triumph of evil is that good men do nothing. --Edmund Burke
It would have been the ultimate asymmetric conflict--can tactical airpower, a far superior army, and an improvised amphib force have won out over tactical airpower, an outstanding navy, and an army that was a shadow of what it had been a year earlier?
I couldn't have said it better.
Even Macksey's speculation about a July "bounce" relied on sealift that did not exist at the time. He assumed German foresight in assembling it starting in late May, while assuming that the British would either not have noticed this being assembled, or done nothing about it.
Alternate histories which assume sudden attacks of common sense by one side are bad enough. Throwing in sudden attacks of ahistorical incompetence (the Royal Navy of 1940 was quite competent save in its carrier leaders) are worse - comparable to alternate histories which give Hitler the sweet disposition of Lassie.
Even Macksey's speculation about a July "bounce" relied on sealift that did not exist at the time. He assumed German foresight in assembling it starting in late May, while assuming that the British would either not have noticed this being assembled, or done nothing about it.
Alternate histories which assume sudden attacks of common sense by one side are bad enough. Throwing in sudden attacks of ahistorical incompetence (the Royal Navy of 1940 was quite competent save in its carrier leaders) are worse - comparable to alternate histories which give Hitler the sweet disposition of Lassie.
Surprised me to learn the Germans had nothing resembling our landing craft. Sea Lion planning relied on motorized and some towed Rhine River barges for both assault and supply. Pretty spooky in the fall with Channel weather so unpredictable. The RAF's survival just furthered the doubts about logistics.
If the Germans had succeded in forcing a landing, our available force was tiny, not only limited by numbers but by available shipping. As it was we rushed everything we could spare over there with the first organized units landing in June, 1942. By the end of September, 1942 we only had 188,497 (79,757 of which were ground forces) in the UK. Planning estimates for five combat divisions with their supply and AAF contingents for Torch were estimated at 427,000 men. That shows how long the logistical tail is.
If the Brits had had to fight a ground campaign on their home turf, whatever shipping we managed to get through the U-boats would probably have been loaded with supplies, not troops. By the end of September, 1942 we had shipped 608, 007 long tons of cargo over there. At the peak rate you could barely maintain five combat divisions which required over 1,000 tons per day each(with their support troops). This doesn't count the buildup. [Source for all this: Logistical Support of the Armies, one of the Army's Green Books. Can you tell I enjoy logistics?]
Would Britain have fought them in the streets; would Stalin have pounced; would FDR have taken the political risk of getting our small force massacred; would Ireland have revolted? Tough questions, but fun to speculate about.