Buying security?

Should Microsoft buy a security software company? Certainly certain pieces of software, such as firewalls, offer many benefits to users if they come pre-installed in hardware, so why not extend that to anti-virus software as well?

One of the key debates in the Microsoft anti-trust trial was "where does an operating system stop"? Anti-virus software is clearly something that traditionally has been outside the core operating system, but may benefit users if it is bundled and integrated into the OS.

As for Win32 API, reader EK writes:

I believe the Win32 API came about with Windows NT, and was an offshoot of what was going to be a joint development project with IBM of OS/2 3.0 which ended up splitting. I spent some time porting software from OS/2 to WinNT and the two were very similar in some ways. Windows95 came along later and was a mix-and-match of Win16 and Win32, as were 98 and ME.