How do you keep something secret when it isn't a secret?
The problem with computer technology is that there are very few 'secrets' in the true sense of the word.
Computer architecture is well documented; and the underlying mathematical and logical concepts are widely taught and understood. So barring some brilliant and unintuitive new algorithm, virtually any computer code could be reversed engineered after observing it's working function. Because once you know what a program does, it's just a matter of coding to duplicate it.
The same thing applies to most military technologies.
Look at atomic weapons. Once the physics of fission is understood, the big breakthrough has already been made. After that it's just engineering - as has been so neatly demonstrated by the recent proliferation of countries possessing or actively developing nuclear weapons.
If the US wanted to keep the atomic bomb secret longer, they should have never called it an "atom bomb." Because once they did, they hung out a great big arrow pointing down a very specific technical path for anyone else to follow. And follow they did.
Unfortunately, there's also another "inconvenient truth" surrounding military technology.
The US (like many major powers) also
sells it's military technologies to what it considers friendly powers. America's so-called 'defense contractors' are also businesses that compete in the international weapons marketplace.
You don't need to hack into an aircraft manufacturer's database to get details on their latest jetfighter. All you need to do is go to an 'air show' and grab one of their brochures. Or call them up and have one mailed to you. And if you still need more information, one of their sales reps will be happy to take you to lunch and answer any questions you may have if you're interested in buying one.
Furthermore, whatever the manufacturer won't tell you can still often be found in
Jane's Guide, which is available at many public libraries.
Sad truth is that most secret weapons aren't really 'secret weapons.' They're just products that come with sales and export restrictions attached.
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FWIW: I doubt you'll ever see any "weapons grade" code up on the Pentagon's website.
Waging war is only part of what the US Military does. Much of the time, it just operates like a very large and inefficient business. And like any big business, it spends a great deal of thought, time, and money on: logistics, training, purchasing, equipment maintenance, paperwork reduction, payroll, and medical benefits.
Plenty of code (and room for improvement) just addressing those areas.
