I'd have thought that wouldn't so much have been a lie, Clint, as an instruction to you to ignore the law.

Here's an article Do Soldiers Have a Duty to Disobey Illegal Orders? by Patrick F. McDevitt an assistant professor of history at the University at Buffalo, State University of New York.

The position seems to be that while the law (international and national) is clear, that soldiers have a duty to refuse illegal orders, in practice, in many countries the people in charge have a policy of disregarding the law, in this respect. Unfortunately, this seems to include the most powerful country in the world, the USA.