For home grown terrorism, how many school shootings happen when the people who know the shooter literally tell police/fbi beforehand about the state of the shooter. Are school shooters not terrorists? They have a social/political gripe and the terror is their way to get their voice out, avenge (like jihad) or inflict change. So why are they failing so bad even after almost 20 years of patriot act?
Politicians don't want to be blamed because they know the next terrorist attack will happen soon and it can't be prevented,except the politicians that gut the patriot act will be blamed for it. On the flip side,information on voters,tracking them like this helps politicians