to use with regard to civil liberties. The argument given in Section II assumes
that an increase in risk is a pro tanto reason for diminishing liberty; maybe not
a conclusive reason, but a reason that should count none the less. The argument
assumes that the introduction of a new set of considerations (along the lines of
“Now we have to worry about terrorism”) or the perception that old reasons
have greater weight (“Terrorists are more deadly than they used to be”) adds
something to one side of the balance of reasons that apply to the issue of liberty.
It assumes that even though there are good reasons for protecting civil liberties,
civil liberties must give way if the reasons in their favor remain the same while
something is added to the reasons on the other side. But this may be misleading;
for in certain contexts, it is not always appropriate to relate reasons to one
another in this simple additive way