For several months after the US entry into World War II, Americans feared air raids or even invasions of the continental United States by Germany and Japan. An article in the March 2, 1942 issue of Life magazine suggested several possible invasion routes that Axis forces might take. These include a Germany landing at Norfolk, Virginia supported by fifth columnists hidden in the US. At the link, you can view maps of a few other fanciful scenarios.
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As you stated even suggesting that something like this is possible, no matter how unlikely, will get people to support the action to prevent it.
Germany never possessed a world class surface navy, so I don't know how this would even be possible
Sorry to see that the American public is just as stupid and gullible as it ever was.
The commitment of equipment and manpower to achieve such a thing would have been enormous and given that the Germans were already heavilly comitted on multiple other fronts it would have been clear to anybody in military intelligence that such an invasion was not going to happen.
I am just saying that the general public does not always take the logical path when fear is involved. I bet it would be very easy to find people that believe Russia could invade the US within a few months. Even easier if some major website posted "plans" of such a things even if it was a joke.
Heh, yeah. Nothing brings people together like a good dose of fear, no matter how irrational it might be.