That's not quite true; the Internet did exist when Macs were first created. The Web did not -it wouldn't be invented for several years yet- and Macs had no form of TCP networking until the introduction of MacTCP, so the Net was basically closed off to them until then. The closest one could get was to use a BBS with an Internet gateway, and these were rare.

Despite this, however, viruses flourished on earlier versions of the Mac OS. How did this happen? Simply put, they spread the old-fashioned way: hopping from file to file, rather than from machine to machine. They spread through the file-sharing sections of BBS systems, and from floppy to floppy as users shared files with their non-wired cousins. It's actually quite shocking just how much of the Mac userbase would infected at any given time.

The old Mac OS was never secure enough. We got some protection from remote hack attacks, simply because the Mac had no network services built into the OS at all, but this severely limited the power of the OS, and it did not close every door. It was a rare Mac lab indeed -particularly in the schools systems that formed the core of the Mac userbase- that didn't have at least one hacked or infected machine.

The world hasn't really changed much, now that I think about it. Permissions are nothing more than correcting a mistake that was made in the original Mac OS: namely, they bring security to an OS which never bothered with it before.

That's part of it, but there was always some degree of security which we needed but never had. OSX corrects that, and if mAxximo's uninformed opinion clashes with that, then I suggest he switch to Windows, where the OS designers think the same way he does about security.