I (25F) am the eldest of three, the youngest being my brother (17). My siblings and I joke around a lot and generally have a good relationship still when this isn't happening. I'm not sure if it helps in any way, but we are Asians.

Around two years ago, my brother started going on a cycle/phase/journey (?) of interests. To give you a general overview, he started with Pokémon, then Zelda, then to various genres of music and then to old Disney stories by the Brothers Grimm. My sister is away for university so it's just me and my brother who get together on weekends and that's when he'd share his recent findings with me. He doesn't talk to our parents about these things.

I'm not gonna lie, it was pretty fun to have a new topic to talk about every week but then, my brother started getting into weirder stuff.

Actually, I don't know if weird is the correct term but basically, he developed some extremist views on certain topics and would refuse to compromise in any way.

Back then, we would at least have some back-and-forth on a topic but just this morning, we walked past a section for toys and plushies in a mall and there were Pokémon so I said, "Did you know, dragonite is a pseudo-legendary Pokémon." to which he said "Yeah but he gets beaten by oddish in Red." I said, "Yeah no, I'm pretty sure dragonite is stronger than oddish." And he straight up rejected me over and over again with "You don't know the lore Ike I do." Whenever I'd try to bring up a point, he'd cut me off and after three attempts at trying to talk, I felt so angry that I gave up.

I'm the type of person to shut down when I'm mad because I really can't control what I say. So, for the duration of an hour, I didn't say anything.

Then, I calmed down and everything was fine again. Another couple hours go by and in the afternoon, he brought up a point about Islam vs. Christians (unfortunately, one of his extreme views) and said Islam is rising which is a concerning matter to which I asked why and he said "They already have the U.S. as a haven, they don't need to have the rest of the world." I replied with "Yeah no, a quick look at recents events would show you that's not true." And he got annoyed when I quoted the kidnappings and racism in plain sight. "Wow, that's so not true. You don't know that they're protected in the U.S.? They're being guarded by secret service." And my mind just lagged for a moment. All I could think of was how did my brother get to this point? Why? When? What happened?

I was already getting pissed off when he talked to me in a condescending tone when he said "You don't do as much research as I do," so I snapped and called him an asshole for his repeated excuse of me not knowing enough about a topic to shut me down. He got mad at me too and called me egotistic for not listening to facts instead of trying to give him my opinion.

I generally don't get mad at my siblings because I feel physically hurt if I do and snapping at him made me feel so bad and guilty. I still feel uncomfortable in my chest while writing this.

Now, I'm just thinking if I should have acted in a more mature way instead of snapping. He's 17 so I know he's in the middle of raging hormones and gets mad easily. Should I have just let it go? What would happen if I go and apologise? Would he feel relief or disgusted or just ignore me? What do I do now actually? As a matter of fact, how do I deal with any future arguments because I have a feeling this isn't the last time.