ももたろうはおにとたたかいました。
If you know the story of “Momotaro (Peach Boy),” you will be familiar with this sentence, which means “Momotaro fought ogres.”
Somebody asked me if たたかいました can be swapped with けんかしました. My answer is “No” and today I am going to talk about the difference between たたかい(たたかいます)and けんか(けんかします).
たたかい is a battle in order to get the better of the opponent.
第二次世界大戦でイギリスはドイツとたたかいました。(England fought against Germany during WWII.)
However, the opponent can be anything.
おじいさんはがんとのたたかいにやぶれました。(Granddad lost the battle against cancer.)
The other party may not be actively involved in the battle either.
ねむけとたたかっています。(I’m fighting against sleepiness.)
Furthermore, たたかい does not necessarily involve negative feelings towards the opponent.
りょうせんしゅともよくたたかいました。(Both athletes fought well.)
On the other hand, けんか occurs when 2 or more parties have different claims over something and both parties try to subdue the other party.
おねえさんとチャンネルあらそいのけんかをしました。(I had a fight with my sister over a TV program.)
If one party has a clear advantage over the other, it is not called けんか.
それはけんかじゃなくて、いじめです。(That is not a fight but bullying.)
If the other party is not willing to participate, けんか does not occur either.
おにいさんはぜんぜんおこらないから、けんかにならない。(My brother never gets angry, so we cannot have a fight.)
Also as the word 喧嘩両成敗(けんかりょうせいばい, “No party to a quarrel is innocent”)suggests, there is no clear right or wrong on either side.
So if you want to say “Police are fighting against gangs.”
けいさつはぼうりょくだんとたたかっていますis OK but not けいさつはぼうりょくだんとけんかしています。
For that reason, you cannot say: ももたろうはおにとけんかしました if you get my drift.