A tourism boycott seems to be in order here.
Really?? And just where would you send your tourism dollars?? Europe??? California?? NY?
Point #1
In order for a boycott to have any effect, at all, the people being boycotted have to know they are being boycotted, and WHY!
Point #2
The people being boycotted have to CARE.
Point#3
The people affected by the boycott must be the ones responsible for the reason you are boycotting, or have leverage on those who are.
I don't see any of those applying to the rhetoric (or even the actions) of a few wackjobs in the Hawaiian government.
But, don't let that stop you, just be sure to call the Hawaii tourism bureau and let them know WHY you won't be going to Hawaii and spending thousands of dollars. And get all your friends to call, too. And call EVERY travel agency in the book, too, and explain their loss of business, due to circumstances beyond their control, too.
Make sure they all understand that they lost their commission because of Hawaii's gun politics. (and not for any other reason). AND all the hotels, airlines, and etc., all the way down to the airport taxi service. Make them aware they're losing money, and WHY. Let them call the Hawaii govt and complain, too.
Oh, and better not order that Hawaiian Pizza, and consider a pineapple free diet, and let Pizza Hut, and Dole, know WHY!
I don't hold any great hopes for your success, but good luck, anyway!