Help interpreting/parsing a tsukkomi retort

Question

I am having trouble interpreting/parsing a portion of a certain extract from an action themed comic :-

Just to give you some context, two enemy factions are battling. Two people from one faction were sent on a mission to 捕獲 the enemy side, they argue a bit at first (let's call them A and B) A was attacking the enemy side with full force but B told A not to kill because their task is to 捕獲, nonetheless B is just as reckless and proceeds to use her full force too. A guy from the other faction displays his power and strength and begins to boast about his abilities excitedly. Then in classic tsukkomi fashion A and B have a little back and forth before B attacks the enemy side again:

A (to the enemy side): ハッタリはそこまでにしておきな！どのみち手前らは死刑決定してんだからよ！

B (to A): だから、捕獲任務なのに殺しちゃ駄目だと思うの……

But what I don't understand is B's line, it doesn't seem to make an awful lot of sense to me in the context, at least in the way I would parse it:

”So, even though the mission is to capture, they can't be killed I think…”

perhaps there is some sarcastic meaning that I'm failing to see because the next line says Aにツッコミの言葉を入[…], so my speculation is there's some hint of sarcasm in B's line to 'correct' A since it's a "tsukkomi retort."

I would love for someone to help me interpret B's line, thanks!

Answer 1

Read 捕獲任務なのに殺す as one action, "(for A) to kill them although this is a capture mission", which as a whole is what B thinks is 駄目. The subject of 殺す is A (because A just said 死刑).

This だから is more like "I told you!", "Oh, come on!" or "You don't understand?" rather than "So" or "Therefore". This usage is colloquial and is not listed on jisho, but 明鏡国語辞典 defines だから also as "相手の発言に対して反抗的な気持ちを示す語".

So B's line is basically "I told you, (you said 死刑 but) I think you can't kill them, coz this is a capture mission."

Answer 2

The 「colloquial だから」

I imagine「だから」is said with the ら emphasized. The usage here is, as @naruto indicated, colloquial.

In conversational English, it's similar to saying

• "That (what you just said) is why I'm doing what I'm doing, so you don't have to tell me. Sheesh."
• That's what I SAID.
• That's what I was THINKING already.
• I KNOW! You don't have to tell me. I was already doing that.