While I would the first to agree with you about the roadblocks the local political class will do to protect HAL, the fact is that airline routes are regulated by the Feds who I can't imagine is any mood to do the bidding of Hawaii these days.  
That said, I'm sure the locals will figure out a way to relegate Southwest to the terminal equivalent of the dog house wherever possible.  But fear not, Southwest has a lot of followers who, among other things, appreciate it free checked bags and no change fees should their plans change.