Apparently they are exclusive alternatives. According to Wired:
Maine is now the lone state not to have been given an extension to long-delayed Real ID regulations, after three fellow protesting states – Montana, New Hampshire and South Carolina – got their extensions in the last two weeks despite not pledging allegiance to Real ID.
What was it Maine in particular did to offend? There is no clue. One might suspect being the easiest to blockade has something to do with it. Bullies like to pick on the weakest victim when making an example.
Assuming no actual bombs get on the plane, then it scarcely matters who the passengers are – particularly since the rules did change in one important respect on September 11th 2001 and few are likely to sit quietly and do what a hijacker says, as they were advised to before that date. If someone could explain to me why any identification at all is needed to board a plane – other than that the government just wants to know where you are going – then I’d be most grateful for the explanation.
[* Yes I know that is New Hampshire, but presumably it is in the line for the DHS's third degree.]