While, personally, I have every sympathy for those who stepped forward and fought fascism (whether Hitler, Franco or anyone else), and do believe that their action and sacrifice should be acknowledged, in this case the fact of the matter is that members of the armed forces of one state deserted their post and went to fight for another sovereign. If members of the British Army had deserted their posts in Afghanistan, the UK or elsewhere to take up the fight against Gadaffi, how should they have been treated?
Hmmmm. US airmen "deserted" their county to fight for the British as well as the Chinese governments. There was some consternation concerning their actions, but they were welcomed back into their own nation's military and came home with a hero's welcome. So in answer to your question, "they" should "have been treated" far far differently than they were and CERTAINLY their children should have been treated far far differently than they were. There's just no excuse or even a remote justification for treating the children of these people in the manner that they were treated. NONE.