Maybe? I guess the difference is that with a capability object model (or similar arrangement) the _only_ way the application has to interact with the outside world is via those objects/handles it's been granted. There's no risk of escape because they only have access to the handles the process has been provided.

It's almost the opposite of a permission model in some ways, permission models restrict access to a global array of functionality where capability models allow access only to what's been provided.