You're talking about two very different things during two very different times.
9/11 was an event witnessed by the public on a massive scale. This was a private development only witnessed by those who needed to know.
You didn't have the internet in 1950s, so even if somebody did know about it and told their friend or grandchild, would that person have found it interesting enough to tell more people.
Lastly, is the attempt to make a UFO really a conspiracy?? It didn't work, so there is very little to report.
9/11 was an event witnessed by the public on a massive scale. This was a private development only witnessed by those who needed to know.
You didn't have the internet in 1950s, so even if somebody did know about it and told their friend or grandchild, would that person have found it interesting enough to tell more people.
Lastly, is the attempt to make a UFO really a conspiracy?? It didn't work, so there is very little to report.