Herr Koeppel seems to be missing the point here. The kind of repressive measures that the founders (left and right) of the Bundesrepublik believed were necessary to prevent a repeat of Weimar had absolutely nothing to do with torture.  These measures included a process for banning organizations, even non violent ones, whose aim was to destroy the basic democratic constitutional order; an internal security agency (Verfassungsschutz) whose job it was to monitor both legal groups who played close to the boundaries and illegal ones already beyond it; strict measures against those who used violence in an attempt to push political viewpoints - hence the hostility to the extra-parliamentary left among most of the SPD in the late sixties and seventies; an exclusion of those with anti-democratic views from the civil service; and a restriction of the freedom of speech that criminalized propaganda aimed at overthrowing basic freedoms.  Anyone reading the excellent comments on Weimar by the various commenters on this thread can easily see why such measures were deemed necessary.

All those measures are being applied against radical fundamentalist Muslims, in addition of course to normal criminal law enforcement against terrorists. The only loophole that existed was special protection for religious organizations, but that has been closed since 9/11. So frankly, Herr Koeppel is either being very disingenuous here, or he's just plain old stupid.

That said, I do find the concept of a Wehrhafte Demokratie quite interesting and worthy of discussion - it runs strongly against the liberal American understanding of democracy which espouses an absolutist conception of freedom of expression and (non-violent) political activity.  Anyone got some thoughts either way?