I think you have misunderstood something. As far as I know no state has ever declared that its own behaviour can amount to terrorism, and one reason for this is that the state applies to some degree arbitrary violence for ideological gain.

I also suspect that there is more to the regulation you're referring to, like something along the lines of 'that disturbs the state, its foreign relations or inter-state organisations'. Is it in StGB? If so, where?