"Would love to hear about ideas though, whether politically correct or not, if you have some."
We are at war with ISIS are we not? A formal declaration of war would mean that those who support the enemy or who attempted to join them are by definition the enemy. The 1,000 who either fought for, or tried to fight for ISIS could be interred until they could prove they were no threat. They could be released on bail only if others from the community could vouch for them and be legally and financially responsible for their good behaviour. Make their families and friends responsible for their behaviour, not the overworked police. Bail would be forfeited if they committed an act of terror.