Hard. Look at the work that went into SELinux. And that is not perfect. There are provably correct programs, but designing software that way will take a lot mor

Hard. Look at the work that went into SELinux. And that is not perfect. There are provably correct programs, but designing software that way will take a lot more time, and a lot more money. The problem here is not technical, we could do it. The problem is that time to market and money are higher priority than security and user privacy for most companies. Educating and motivating users to use the features of such an OS in order to maximize its security (e.g., capability bits)? So much harder. This is, in my opinion, the more insurmountable problem. Most users have no idea what a window manager is, much less how to change their window manager. Security requires someone to set the capabilities allowed based on what's needed, with fine grained security controls. That takes more time and effort. How many of you have deny all on site permissions in your browser, and only enable the ones you need for the sites you need them for? And we are the technical audience.