UPDATE: Oh my gosh, I have loved reading every single comment on this post and the discourse has been amazing! I love you all!
I most appreciate the comments from u/blakeh95 who has been super informative and insightful.
I've had a couple days to think all this over and discuss my feelings with my therapist.
Overall, it seems that rules significantly vary between different states and locations, as well as many "laws" being a bit subject to interpretation.
Fortunately, I was able to find a great document from my jurisdiction that explicitly states that because we both had to wait for cross traffic to clear, it was irrelevant who pulled up first. In this situation, he ABSOLUTELY needed to yield to me going straight before he turned left.
I feel so vindicated! And I have officially ruled myself NOT THE ASSHOLE! However, it's probably best we all slow down and communicate better with other drivers so that awful road rage events like this, or worse, accidents, don't occur at all.
I hope that fellow had the day he deserved!
Thank you all again <3
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Had a delightful (/s) mild road rage incident today and need help determining if I was indeed the asshole here.
Two way stop on a busy road. He pulls up to the stop sign across from me first, signalling left. I pull up to the opposing stop sign second, going straight. Once cross traffic is clear, I start to go (as I'm going straight, despite pulling up second). He guns it, fingers me, fishtails like a moron, rolls down the window, fingers me again from behind, and then speeds off.
Who had the right of way in this situation?
A: Me, because I was going straight despite arriving second.
B: Him, because he got there first, regardless of direction
C: He's an asshole even if I was in the wrong because there was no need for him to react so childishly.
I appreciate any and all responses, thank you so much!