What's the alternative to preventing a bunch of zealots turning the US into a war zone? One in which subways. restaurants, and shopping malls are bombed at will? If Preemptive actions like those in this report are illegal then what choice do we have but to wait until an attack is carried out?
Perhaps that's what it will take to maintain our liberties. Allow those who would destroy our liberties the freedom to attack. However, will the American people sit back and let the police handle it like other countries already experiencing regular attacks by Islamofacists do? If the attacks continue unabated it will likely mean the eventual expulsion of all muslims thus denying us one of our prized freedoms, that of religion.
Either way, it seems we lose liberty.