Which "mentally unstable" people? Veterans who simply had someone appointed to help with their finances? Your claim is needing a second set of eyes on a checkbook is a predicate to violence? Got any evidence?

As for the "terror watch list." What other secret lists, onto which a person, legally innocent of any crime, can be placed with no due process and no notification, essentially arbitrarily based merely on having a name similar to a suspected (not proven) "terror involved person", which person is then utterly ignored by law enforcement thereafter, not tracked and often never actually being investigated, which list can be difficult to be removed from if the person happens to discover they are on it, do you support as a basis for revoking rights? 

It would behoove you to do more than repeat talking points from anti-rights zealots. At least then you'd be on the side of the ACLU and the major veteran's and mental health professional organizations.