In answer to Jackdaw's question about David Davis's views on Begum, the clear reasons that Davis "wanted"* Begum back were: so that she could face justice for her crimes; so that she wasn't left in a country and potentially at the mercy of terrorists to radicalise her (and, when he wrote about this a few years ago, her then-living child) still further; not doing anything about her and others like her risks antagonising the US. In any case, it certainly wasn't because he was happy to see a terrorist, or a person associating with or raised by terrorists, to run wild and free with all the consequent risks that would have posed, and I don't see either that it was out of sympathy for her lot. At most, then, it seems to be stemmed from a rejection of the idea that "out of sight, out of mind", and a belief in the authority and decency of British Justice.
It should be stated that I am interpreting, as best I can, Davis's views, and I'm not expressing my own in this post.