http://www.pbs.org/wgbh/pages/frontline/cheney/view/
this link take you to a frontline program on cheney/addington and their legal theory of de facto dictatorship, which they reference as the "theory of the unitary executive."---again, this is straight carl schmitt, but with the rhetorical references stripped away.
that it is permissable within the existing system is a problem within the existing system.
one thing i think the bush people have taught us is that the power of the executive can be a Problem if the right right group of neo-fascists get access to it. another thing they *may* have taught is that this possibility--the "unitary executive" tipping toward a theory of dictatorship--is enough a problem that a basic rewrite of the rules might be in order.
in a more rigid type of constitutional system, like you see in continental europe, the bush administration would have already triggered a constitutional crisis. i am not at all sure that the inability of the american system to register crisis is a good thing. i am not at all sure of that.