Firewalls prohibiting working at home

I've been working from home quite alot recently and the corporate VPN my boss provides has been quite helpful. However I think we need a bit of a paradigm shift before we all can truly enjoy working from home when we want to. And it doesn't even fibre for all, just a different kind of corporate IT-security department. I also had a word with some colleagues and some of Logica's IT-architects are arguing against firewalls and defining a strict internal and external view of company IT.

The result of not having an internal or external view of company IT, would be that a system is either safe and trusted and can be accessed from anywhere by authorized users or a system isn't safe and it doesn't matter whether it's in the corporate perimeter or not. (one of the assumptions is that if you run a large company like some of our clients, inside is almost as hostile as outside as corporate espionage is a risk)

The effect may be that it doesn't matter where personnel lives/works as long as they can access the systems. Of course there are other objections against not seeing your colleagues, but on a day like today when we were supposed to be snowed in, being able to work from home can be a production saver.

An example, my wife works as a credit management consultant for different clients every 3 to 6 months. She always has to drive to the client as they don't trust her to tele-work (you know corporate IT security). Yet she has complete access internally... Now how is that different?