Archeologists and geologists might disagree. Yes, thats why we examine geological record, anthropology, philology, ect. Not just scripts and texts.
My cousin has a bachelors and PhD in architecture and a masters in industrial design from a top school. He can explain the pyramids better than I can. But long story short, it wasn't aliens or whatever. But I can give it a shot, if you'd like.
Its hard to hide construction projects of the magnitude of Mt. Yamantau or Cheyenne Mountain. Plus the resources needed. I do, however, find things interesting like Soong Dong cave discovered in 1990. I'm sure the government has secret bases in remote areas. But today it's hard to hide anything from satellites. The NRO's job is to track enemy nuclear submarines, for example. They have ~100 satellites more powerful than the Hubble scanning earth all the time. (I can link to this).
Was there an Atlantis? Sort of, off the coast of Greece.
Both Plato and Socrates are historical figures widely accepted to have existed. However, like many figures from ancient history, there are occasional fringe theories or skeptical viewpoints regarding their existence. These viewpoints are not widely supported by mainstream scholarship, which overwhelmingly affirms the existence of both Plato and Socrates based on historical texts, archaeological evidence, and their significant influence on subsequent philosophical thought.
Cemetery Wind is an example, NRO is an example, Delta Force is an example. I'm sure there's other units. Maybe not entire branches of the military, per se. But after 9/11, PBS discovered that over 1,500 agencies were created, over 2,000 companies were contracted and over 1.5 times as many people who live in DC were granted Top Secret clearance. The government didn't acknowledge the NRO and Delta's existence until the '90's. The CO is kept secret. The budgets are classified, same with the CIA's. The Pentagon has a separate black budget.
All black projects (super secret) are funded beyond the "experimental" budget items, by including funds in other projects, so these projects provide "shelter" from direct oversite funding. They really did not pay $400 for a hammer. Projects like the the F-35 could actually be an intelligence community money laundering scheme for slush funds. Or it could be a hybrid (being delayed so they can put money in continuously while siphoning most of it off for other uses, but still progressing to an eventual conclusion). Or it could be just a colossal boondoggle kept alive to keep jobs alive in various key congressional districts.
They didn't keep nuclear secrets very long. One of the key scientists working on it was a Russian spy.
I personally like to deal in the world of facts and empirical data.