That's true, but ...
E.g.: The Department of Health, to operate properly, needs to have records on you. They can share those records.
N.B.: While in principle it should be possible for the end user (patient) to have control over those records, in practice a large number of separate people (medical specialists, at least) need to be able to access them simultaneously. This makes real security of the information impossible (or at least I have no idea how one could do it). And THIS means that as more and more information is needed by the Department of Health (e.g., your DNA sequence) and as advances allow more and more to be done with the information (e.g., your DNA sequence)...well, eventually other parts of the government will be able to access that information, and use it to produce an estimate of how you will act in various situations. (It need not be accurate for people to do it.)
P.S.: There have already been attempts to categorize people as "proabale criminals" purely on the basis of their DNA. So don't think it will never happen. It may never be accurate, but that's a separate question.
Anyway, because of this, it makes sense to consider the government as a unitary entity, even though the various parts of it don't coordinate. It's probably more of a unitary entity than is a sponge, though possibly less so than is an earthworm.