I don't think you're getting very good answers here, but the real answer is there is a split between strategic and tactical intelligence (and operational, but t

I don't think you're getting very good answers here, but the real answer is there is a split between strategic and tactical intelligence (and operational, but that's kind of in the weeds to distinguish from tactical). Military departments don't generally operate their own strategic intelligence assets. They get the information they need from the CIA, NSA, and NGA, the same as the president and anyone else who needs that level of information. At the tactical level, though, military units need to be able to operate fairly autonomously. This can go pretty deep down. It means a division of the Army may have aerial recon assets, signals interception devices, and such with an operational range of, say, 500km or something, but not things like spy satellites that can cover the entire globe. Down at the company level, they may even have their own assigned scouts with some limited remote recon tech, but then the range will be much more limited. The point is they can use that stuff within their own area of operations without needing to deconflict with other users, having full local authority over tasking. Tasking of national strategic assets like spy satellites, on the other hand, needs to be done at a level of clearance and authority that has visibility into what all of the nation's military units are doing at any given time, as well as some idea of what they're going to be doing in the future. This is why we have national intelligence agencies, but each branch of service and even individual combined arms units also have their own intelligence sections. It's similar to why local police departments have their own detectives and don't just ask the FBI to perform all investigative duties for them (more to it in law enforcement because there are also different laws at each level of government, but still some similar ideas).