There's two types of ISIS ladies
- The ones caught in the crossfire who had to pick sides locally and can't be blamed for being stuck in a warzone
- Those that lived in Belgium/Holland/UK/US/France etc. had seen all the horrors on the news but hen answered the call to travel to Turkey and from there to Syria.
They volunteered to go the 'Heimat' of the new Islamic state of murder, slavery, genocide and butchery and willingly breed new soldiers.
They're not only a security risk, they have no future in the west at all. In fact, they renounced the west by leaving their peaceful lives for one filled with war and adventure.
These people did not end up in this war 'by mistake' but took the steps willinglly to go there. Ignoring all the pleas of their governments and community to not go.
Most of them burned their passports to show their allegiance to ISIS. There's no reason for us to take these people back in.
They would likely be happier in a (less radical) Islamic country or they could join John McAfee's campaign in exile.
Also, a trial is impossible because ISIS didn't keep detailed records of their killings. And finding witnesses of acts commited by genocidal maniacs is kinda hard.