halacha - Self-defense in a street fight?

I was in a situation where someone basically approached me indicating he was going to fight me, squared up with me, stared me down etc. pushed me twice, and then I thought to myself, "If he raises a fist, I'm going to hit him", based on the Gemara(Brachos 58a), "if one comes to kill you kill him first", and that is exactly what happened.

Was that allowed according to Halacha?

Perhaps I could have turned and ran, but the situation didn't exactly call for that, and I couldn't be sure that I wouldn't have been punched from behind (extremely dangerous)...

Answer

I had this situation once. It actually got physical. Story time folks. For those who want to skip to the psak that answers the question, scroll down to the last paragraph.

Boro park in the early nineties. I had just gotten down the block after davening by the early minyan on Motzei Shabbos and just took a couple of steps into the street when some guy who was speeding like a lunatic almost ran me over. He actually had the nerve to stop his car and start yelling anti-Semitic slurs and how 'if we wouldn't always dress in black he could've seen me'. I still said nothing. Apparantly this wasn't enough for him and he started dancing in front of me with his fists up like he thought he was a boxer or something. There was nobody there to call for help. I did what I had to do. Bisiata diShmaya I landed two solid shots straight across his jaw. This left him reeling for a moment. Long enough for me to start going on my way. Then this guy started yelling for more. I turned to see he was weilding his CLUB (remember those?) Like a baseball bat. At this point I ran! I got two blocks down before he caught up with me and jumped out of his car again with his CLUB. Now I was scared. But then I was zocheh to have almost simultaneously all 3 Chassidishe shuls on that corner let out of Maariv. You should've seen this guy's face when he saw hundreds of Jews in black pouring into the street. Back in the car speeding home to Bensonhurst he went.

The next day I felt bad and asked my Rosh Yeshiva if what I did was proper. What if this guy goes and takes it out on some other Jew? He told me I did the right thing and hopefully he was taken care of well enough that he wouldn't start up with any other Jew ever again.