My understanding is that the correct way for an AG to do this is to notify the President / White House first, as in, "I cannot in good conscious enforce this. I would be happy to discuss it with you, and/or provide you with my resignation".
Instead, she just sent out an email to nearly 100,000 civil servants telling them not to enforce it. That is insubordination at best. It may be childish, but I turn all these incidents around to, "What if they did it to Obama?" Because all the complainers would be screaming bloody murder (and did) if anyone in govt dared "resist" Obama.