Thought I'd make a throw away and tip in as there are lots of people here who've never had a clearance and don't really understand what it's all about (I've had one for more than a decade). I'll try and answer some questions in the threads as I can. In the U.S. here's how it works (I'm writing this from the perspective of a contractor): You are hired to work on a government contract, that contract requires you to wor…
There are many many networks, agency specific ones, site specific ones, standalone networks of half a dozen computers (say for a SAP program), sometimes some that give access to different compartments, etc.
Even at the Secret level, you have access to a mind-boggling amount of information. There's nothing particularly surprising at the amount of information Manning had access to. I'm surprised he didn't make off with more to be honest.
I've also found a couple things to be true about moving up in classifications for those that are interested:
1) The higher up you go, the lower tech things tend to get. The IT systems on super duper squirrel SAP programs are positively ancient. There's no super secret A.I. computer that only the President and a strangely well groomed computer super nerd know about. It's probably a 10 year old desktop with a slightly broken CRT monitor.
2) There are some really cool toys at high classifications -- neat space cameras and all that. But the vast majority of the really neato stuff is at the Secret level. All the tanks and bombs and military toys are pretty much at that level. "The Army Fights off of SIPR (the secret network)" is the mantra. If you go to Wikipedia and start looking around at various pieces of military equipment, you'll probably seen 95% of the toys that anybody with a clearance has authorization to know about.
3) This piece is absolutely true, and the voices that speak in loud tones about vast conspiracies but who've never been in this world are perfect examples of what this article is talking about. Once in, the utter mundane nature of most of it is almost overwhelming.
4) An amazing, astonishing, amount of information is available completely for free on the Internet and in Libraries and other completely open places. Often the best information comes from there. There's even a field called "Open Source Intelligence" that requires no clearances at all! It's basically internet surfing and report writing to answer specific questions like "does the Prime Minister of Japan have a mistress?" or "what kind of space launch capability does the Ukraine currently possess?" or "what's the phone number of this Falafel joint in Paris?". Some of the best, most insightful, and most comprehensive stuff I've ever seen was put together with access to the Internet, MS-Word, Google Earth/Maps, Powerpoint and a Library Card.
Here's a great example: http://www.nkeconwatch.com/north-korea-uncovered-google-eart...
5) Physics applies even to the Intelligence Community.
If you have a decent education in Engineering or Physics, you probably already are capable of knowing or understanding 99% of the capabilities of the highest of the high speed super spy systems. If Physics doesn't allow it, there's no getting around it. That doesn't mean people haven't engineering some clever things, but we're still limited by things like the speed of light, or available materials that can defract or focus it (none of this "enhance, now focus on the reflection, enhance, now that reflection, enhance, rotate, enhance!"). Radio waves can't penetrate the earth, low frequency waves that can penetrate lots of stuff still propagate to the inverse square law. Encryption can be broken, but it takes lots of computation power to do it often enough -- being able to break a single message in 12 months with a top 100 supercomputer doesn't mean squat if you need to break a million messages a day.
http://en.wikipedia.org/wiki/Radio_propagation
6) Almost everything I've said here is on Wikipedia, or linked to by Wikipedia. Anybody really interested in this stuff, and determined enough to click link a few dozen times could figure this out. It's often surprising how passionate and conspiratorial some of the most uninformed comments are, even here on HN where there's no excuse to not have done just that.
7) Getting a clearance is really not that big a deal, but there can be a catch-22. Most jobs that require a clearance won't bother letting you apply for one. But there are still plenty of places out there that do. Lots of R&D organizations will do it. Non-profits that contract with the Government will often do it. It's easier to start young, the investigation is faster. But the reason most don't is that they likely have nothing for you to do without a clearance and you'll just be sitting there eating up overhead budget for months on end while you wait for the process to work its course.
8) Security managers, (FSOs and SSOs) are almost uniformly idiots. If you think Comcast's customer support sucks, try dealing with these clowns. Misfiled paperwork, nonresponsive to emails and phone calls, generally don't know their jobs, etc. If you find one who has half a brain you hold on to them lie you are drowning. The only thing they are good at doing is making sure that people without tenacity are filtered out of the system.
9) This job often sucks. Paperwork you can't believe, endless training lectures, shitty work environments, old IT infrastructure, endless hassles to get to do your work, constant barriers to just getting things done, weirdo people, lots of unmotivated do nothings, no windows, can't talk about work, forget one of a couple dozen passwords, cut off from the outside world most of the time, no idea what the current news is most of the time, pay can often suck compared to private sector, access to data is usually buried in some non-machine readable format.
10) The job can be rewarding. More than once while I was doing work, stepped out for a break and saw some breaking news on CNN or someplace that was reporting on recent evens right where I was! Cool shit. Other times you get to play with tremendous amounts of raw data, if you are a data junky it can rock. Cool toys, things used in ways you probably won't believe, gather and collect that data. And sometime really incredibly interesting people who've been around this stuff for decades. Some of the smartest people I've ever met work in this field, outright 1 in a century geniuses. And savants who've memorized the chemical makeup of every piece of military hardware in North Korea's arsenal, who the current commanders are of all the tank battalions and can draw a spectrograph of all of the elements by hand on a whiteboard.