2011: The Year of the Rabbit.

Clearly "Mary Poppins" got made, too. At least, I personally know now prior art which would explain the Nanny.

That's a tough part of making any Alternate Reality fiction, isn't it? If your superheroes/magic/etc. isn't a secret that is completely hidden from the world, then it would change a whole lot of the mundane world, and pretty soon a whole lot of that world doesn't make sense. If you're the sort who studies history and notices how these things all affect each other, of course.

Actually, the Nanny could have been based on the book Mary Poppins. But there probably was a movie--based on my reading of Velveteen vs the Flashback Sequence, the public-visible "zero hour" didn't happen that long ago; probably around the same time as the 1964 movie (more or less; could be as early as the '40s). Recent enough that Supermodel was appropriately called Supermodel, and there was enough of a spin doctoring setup to rebuild the Super Patriots after the early, tragic events happened.

I was not aware there was a book! Guess I should have looked it up.

I get the impression, perhaps false, that many of the superheroes existed well before Super Patriots showed up, but they weren't as public. The "zero hour", seems to be more about publicity than existence. I also note that Super Patriots seems to be leaning heavily on the rather insular nature of American culture; to my knowledge Seanan hasn't really mentioned one way or another about non-US heroes, but surely they exist. One might speculate that Super Patriots tends to try to avoid mention of these, and keep the notion of heroes who exist or have existed independent of Super Patriots, away from the public awareness.