Ok, a question asked......
I guess the most basic way to think about it is security.
While no single organization, U.S. or otherwise has the corner market on being totaly secure,
they do put forth the effort.
So, the "net" seems to be this mysterious form of communication that everyone has a theory about,
but the truth is much simpler.
I always look at the network like a spiders web.
The first thing a spider does in its' construction is to anchor a few main lines. Think of these as the "backbone".
Next, our little friend ties the backbones together, linking them with a series of shorter lines, each one tieing into a backbone line
at each end. You can think of the tie-in points as switches, or "hubs".
Now believe it or not, or little 8 legged wonder knows where each hub is. This is in case repair work is required.
Also, the vibrations that the spider feels are carried thru the "backbone" lines and resonate thu-out the web.
Ok, enuf of the bug lesson. Basicaly, if you had the man-power, knowledge, and authority, you could tap directly into a backbone line and see what is resonating from all the other hubs.
Thats what they have, the knowledge, man-power, and authority. Of course, each country has it's own version of this little team, but you get the basic idea.
Because of basic security issues, being able to trace someones precise location via a web connection is usually reserved for those type of teams. If it were possible for everyone to do it, keeping world learders secure would take on a whole new meaning.
At our level, (and I say our level in the broadest sense), we can usualy trace an IP and get a general location of country and township, but remeber, the location you are seeing is where the "swithch" or hub is that the IP is being carried from, and NOT a street address of the user. With proper aplication of this information, you are able to report abuses however. Most networks have an abuse contact listed. Just log all the info pertaining to the abuser, what the abuse was, and all the trace steps you recorded and most request that to be emailed to the abuse reporting address.
Well, how is that for an answer? Too long? If so, stick with Papajohns reply