My focus is not to see her hanged, although I wouldn't lose much sleep if she was. It's to point out the enormous (though totally predictable) double standards coming from "ulra-lefty" types, as you put it. Many posters here are totally convinced that she's a victim, despite the fact that she travelled 3000 miles to join a genocide cult; and that the government's stripping of her citizenship was illegal, which it very clearly wasnt. Change the sex, colour, and probable motivations and I promise you, this thread would look very different. There's also a huge arrogance in the notion that only a British court could deliver justice. Why? The crimes of the organisation that she joined were primarily committed in Syria and Iraq, where she was ultimately detained. If I was arrested for the murder of a French citizen in France, would you argue that I should be sent back to London to face British justice?
She may have been coerced into joining IS. She also may have wholeheartedly sought to join them and involve herself in their pogrom.