10. "Yes, Prime Minister"

"It recently came out in released Cabinet Office documents in the UK that, in 1984, a French security officer placed two REAL bombs in the grounds of the French Embassy in London, in advance of a visit by President Mitterrand, in order to test British security. He just casually carried them past British border checks by telling them he was an intelligence officer.

Sound familiar? That's because it became a story on the sitcom 'Yes Prime Minister.'"

RedWestern

9. Failed surprise attacks

"Operation Unthinkable, the plan for the UK and US to launch a suprise attack against the USSR at the end of WW2"

MaterialImportance

8. What else are they spending money on?

"My vote would be for the Mars remote viewing document declassified by the CIA. Even if it's something made up by the remote viewer, WTH is the CIA doing spending money on this kind of stuff?"

gripto

7. These kinds of stories are becoming all too common

"Kincora Boys home. A boys home in Belfast NI where a lot of high profile politicians and even royalty are said to have abused the boys. MI5 are supposed to have known about it and used the info to blackmail people.

what really went on that the govt wants to keep it secret for another 65 years?"

Wenge03

6. A potential nuclear tidal wave

"A 2015 declassified Russian document verified the existence of a drone called the Poseidon drone. This is no ordinary drone, it is an underwater drone containing the largest nuclear weapon ever created having a yield of 200 Megatons, 4 times larger than the Tzar Bomba the largest nuclear bomb ever created. Furthermore, it contains a cobalt style bomb which when detonated unleashes a 200m nuclear tidal wave which can destroy any coastal city in it's path. Just for context the 2004 Indonesian Tsunami had waves as tall as 20m this is 10 times larger and full of dangerous radioactive material. Obviously this is a last ditch effort but it makes me think, if this is declassified what horrors still remain classified."

nova3482

5. This is arguably common knowledge 

"The document declassified just a couple weeks ago, the war in the Middle East that we've been fighting for over a decade is completely unwinnable and they've known this for a majority of the war."

EffectivePineapple2

4. Where are the bombs!?

Basically every Broken Arrow incident, especially the ones that occurred during the Soviet collapse. The idea that the military can just lose track of a nuclear bomb, a miniature sun basically, is already terrifying, even if most of the devices are recovered. However, Russia lost track of about 200 nuclear bombs after the collapse of the USSR, and they STILL have no idea where they are! I understand that the Soviet union fell apart in the 90s, but since so many of their nuclear bombs are still unaccounted for, I consider it an ongoing crisis

Flappybird11

3. Pure evil and scary

"Operation Sea Spray. The US Navy literally released pathogens in San Francisco in order to affect the whole population, just to see what happened. A lot of people developed diseases like pneumonia and UTIs."

QuirkyPheasant

2. Staged terrorist attacks

"Personally, I would say Operation Northwoods. The fact the the government has no qualms about staging a terrorist attack and killing its own citizens is scary."

flameguy4500

1. "5 Eyes" sounds so sinister 

"5 EYES

Whenever the country you live in needs to spy on it's own citizens they ask another country to do it for them, completely circumventing any percieved "rights" to privacy, a fair trial or due process, among others. Also sharing among member and associated states, if reports are to be believed, beyond-cutting-edge technology that frankly borders on science fiction."

CapsLowk