They why is it their job to condemn Constitutionalists?
It's not, and they haven't.
Sure sounds to me like they did.
Did you read the link in the OP?
From the FIRST PAGE:
To be clear, the National Consortium for the Study of Terrorism and Responses to Terrorism (START) does not classify individuals as terrorists or extremists based on ideological perspectives. START and the Global Terrorism Database, on which the Report is based, defines terrorism and terrorist attacks as "the threatened or actual use of illegal force and violence by a non-state actor to attain a political, economic, religious, or social goal through fear, coercion, or intimidation.