I am also primarily a utilitarian thinker. What has me considering the deontological position on this specifically is that, for utilitarian purposes, I have voted to allow our entire federal government to continue to drift right. When choosing the lesser of the two evils every time I did, I think I failed to consider that my permissiveness would embolden the lesser of the two evils to become increasingly evil as they were aware I wasn’t voting for them but against their opponent. I gave them license though my voting behavior to move to the right as much as they wanted and be financially rewarded for doing so because they knew they would always have my vote as long as they weren’t as bad as their opponents. This genocide is a red flag to me that since I have been voting to avoid immediate consequences, the ultimate consequence is that some of those consequences I was afraid of are now guaranteed from both options to varying degrees. The more I have rewarded the Democrats with my vote which they need to be elected, the only thing they need from me, they have no incentive whatsoever to do anything but what benefits themselves just as long as what they do isn’t as bad as what the Republicans would do. Average people aren’t funding their campaigns, we are only handing our votes over to them because their opponents are worse, despite both of them becoming worse all the time.
When I talk about whether to grant or withhold my vote to my only actual option, it’s a matter of currency and power rather than morality. I have found that if I always grant my vote regardless of the behavior of who receives my vote, they know they have license to do the things they were doing when I voted for them and no reason whatsoever to change course according to what I would like to see and not see, such as a genocide.
You are absolutely right that there isn’t an option for president outside blue and red. Our system isn’t built for it. Blue knows I’m not suicidal and can’t vote for Red, so the question becomes whether or not I will tolerate them becoming worse every cycle as long as during each cycle their candidate isn’t as bad as their opponent who is also getting worse every cycle. The option is whether to support Blue regardless of what we do and watch the system deteriorate, or demonstrate to blue that there are limits to how far right they can move regardless of who they’re up against with the hope that at least one side will stop getting worse because there are still consequences.
The reason I want to stop this cycle is survival. I think we are guaranteed to drift into explicit oligarchy as long as both sides are allowed to continue moving rightward. Every election since 2010 has been worse than the one before it, and I don’t think there’s a reason that would change after this cycle. The Republicans are going to try to capture the appeal of Trump even though they haven’t yet, and the right wing runs on delusion so they aren’t accountable to anything. All they have to worry about is telling lies that people strongly want to believe. The Democrats have to contend with reality and in my view are party far more likely to react to something that happened here in real life so they have better chances at being elected in the future.
I will easily concede that this is awful timing. Trump is a massive threat as you described. If I thought he would be highly successful in everything you mentioned, I would not consider doing what I’ve been advocating for. Even though I know him to be incompetent and without much support outside his base for anything he wants to do, any amount of success he has will be a problem. The primary reason I see fit to act as I described is because I predict the 2028 election will be between someone who is to the right of Biden vs someone who is to the right of Trump, and every future election it will be more and more difficult to change course from where we’re headed. All future elections could be about how appealing Republican lies are vs how many people don’t want them elected and are willing to vote for anything else.