I don't know if COM and DCOM comes from CORBA,
It doesn't.
With COM and ActivX the API gives your app access to the memory space of the ActiveX component, which again use a shared system bus. If you plug into the Windows system bus, you can see all messages gong around. You can intercept messages meant for other applications,
Complete rubbish. Windows is a full fledged protected mode OS, applications are very much shielded from each other - yes, I believe Linux is superior but due to differences far more subtle then you are describing.
With the message busses used on *nix systems you cannot do that, because there are diferent busses and you can only access what the bus allow you to see.
This statement is so vague as to be meaningless. And many of the messaging technologies used by X-windows environments over the years have been horribly insecure.
Look at technology common to Windows & *nix, say Java: how much less secure is Java on Windows than Gnunix?
Very much. Due to the common message bus that Windows use, the java application potentially have access to any other application,
Bogus.
What started this conversation no one has addressed: the primitive [absent] interactive GUI "Firewall" technology available on Windows.
I think you are still not getting the point.
I think YOU are entirely missing the point. An interactive firewall IS EASIER TO USE! Otherwise apps silently fail to work - this has nothing whatsoever to do with worms, viruses, trojans, etc... It has to do with informing the poor user what is going on. Lack of such a feature on the LINUX desktop IS a deficiency no matter how you want to spin it. Like no feedback for offline print queues and the inability to edit filesystem ACLs in the GUI.
You percieve Linux as being primitive because it does not feature a useless application that can only give you a false sense of security.
I don't percieve the LINUX desktop as primitive, but it certainly has functionality gaps that still need closing. This is a legitimate user need.
The point is that you should first look at where the real threats are on a Linux system and then think from that angle.
The inability of the system to INFORM the user that it blocked an applications attempt tp communicate is NOT a "security" problem, it is a usability problem.
On Linux you should NOT focus on a tool that can tell you that you HAVE ALREADY been compromised.
Because an app is trying to open a port means you've been comprimised? Again - Bogus.