What he was doing in Syria was not fine, but whatever he was doing he was not doing it here and it's here where out jurisdiction begins and ends. He was not an enemy combatant as this country is not at war with ISIS, so the Muslim Council of Wales, and all of us for that matter, need to know on what basis this decision was made.
Cameron consulted the Solicitor General Robert Buckland, Tory MP for South Swindon on the legality of the attack and was told it was tickety-boo, it'll be interesting to find out what the legal justification was.