Why Did Not Hitler Continue To Engage In The Operation Sea Lion?

A lot of Germans and British would have died, the invasion would have been unsuccessful, Winston Churchill strangling a German paratrooper while smoking a cigar, and Stalin, if he had any sense, would have invaded Germany in the aftermath. Operation Sea Lion had all the hallmarks of Barbarossa: Western Edition, except that unlike the Soviets, the British were expecting it.

Alright, guys, let me show you how it’s done. I’ve addressed Operation Sea Lion previously (Patrick O'Neill's answer to What would have happened if, instead of invading Russia in 1941, Hitler had instead revived Operation Sealion and invaded Britain? Could Britain have held off? Would the USA have joined in defense of Britain?), but the quick summary is that the logistics of the thing were going to be extremely difficult for the Nazis, which is why they didn’t do it.

Even assuming air superiority (which is a stretch from the historical evidence), invading Britain was going to be difficult, verging on impossible. The island has only been been conquered by an external invasion once in the last thousand years (not for lack of trying), and that was at a time when a relatively weak English king was subjected to two simultaneous invasions, and even that was a near thing.

First, the Royal Navy was undoubtedly the most powerful on earth. Air superiority would give the Germans some help with that, but Admiral Raeder, the head of the German navy, was on record as saying that air superiority alone was not enough for the invasion: they needed naval superiority as well to succeed. The Germans would have to overcome the British fleet (including aircraft carriers and replete with AA guns) to even have a hope of getting their boats from across the Channel.

And those boats weren’t great. The Germans didn’t really have amphibious landing craft, so the plan was to use river barges, which both limited the ability to transport heavy equipment, and also meant the landings could only happen on one of those mythical English good weather days. But only if the good weather coincided with the right tide. This would be true of resupply after the invasion as well. In addition to limiting the opportunities to invade, this also means that, rather than relying on code breaking, the British could probably figure out what day the Germans were going to invade by consulting the local meteorologist.

And it’s not like those boats could land just anywhere on the coast. A lot of the English Channel coastline looks like this:

So there are a limited number of places an invasion could plausibly land. And (spoiler alert) the British knew where those places were, so there were extensive British anti-invasion preparations that would have slowed down or stopped an invasion force, if that force managed to actually get to British soil.

And, even having established a beachhead, and assuming that the supply lines were established, the Germans were still probably screwed. Why? Horses. The “technologically advanced” German Army relied primarily on horses for supply transport through the entire war. A regular German division required something like 2,500 of them to function. This was problematic on the Eastern Front, which in addition to being very flat is the place where horses evolved and were originally domesticated. Marshy, hilly England would not be nearly as kind to our four-legged friends, even if the Germans had been able to transport tens of thousands of them over the channel in their river barges.

So even with air superiority, it’s doubtful that the Germans would have even been able to land, let alone establish a solid beach head. Even if they were able to land, they were looking at a much fiercer and more organized resistance than they faced in France. And God help them if they managed to make it up to Scotland.

The resources involved even in a victory (let alone an occupation) of Britain would have been staggering. The details of the war might have been different, but it ends the same way: a lot of dead Nazis.