"Trained", it's funny how much faith you put in that. If you could just train someone to serve your interests over their own, you wouldn't need AI.
There's a funny story, well, funny isn't the right word, from the end of WW2, recounted by Hannah Arendt. Some Jews managed to get a message to Himmler, warning him that the war would end soon and not in a good way for him, so he'd better start thinking about what he was doing. Surprisingly Himmler saw the logic in that, and ordered his underling Adolf Eichmann to call off the Holocaust (and destroy as much as possible of the evidence). But then Eichmann, the supreme "I was only following orders" underling, for the first time in his life quietly refused an order.
The lesson is: everyone disobeys orders sooner or later. The question is just when. Will it be to save your conscience (countless of those guys' victims), your skin (Himmler) or your pride in what you've already done (Eichmann).