Six months ago, Daniel wouldn't have thought even once about killing that tank of defenseless Goa'uld larvae. It wouldn't have even crossed his mind.
But six months ago, the Goa'uld hadn't ripped Daniel's very heart from his chest. He hadn't felt the rage of being just too late to prevent them from taking Sha're. Six months ago, he'd barely been able to fire the gun he now swung with practiced ease to aim at the tank.
After the mission, when the adrenaline of finding Teal'c's family and fighting their way back through the 'gate had faded, he'd expected to feel something. Some… guilt, or something. Some recognition that he'd executed mere children, innocents, practically on a whim.
But there had been nothing. He'd gone through the post-op examination as usual, and was halfway through writing his report before he even thought about it.
When he ran into Carter's lab minutes later, and panting and out of breath, leant for support on her desk, and gasped out: "Why did I do it?" She looked at him oddly. But she was a soldier, he should always remember that and he wasn't sure why he'd thought she'd understand.
"Daniel… every host that those Goa'uld would have gone on to infest would have been someone's parent. Someone's child. Someone's Sha're."
"But…"
"No, that doesn't vindicate what you did. But it's done, and if any of us had reason to kill them… you do. I can't pretend I understand Daniel but I know you're still hurting over Sha're. You can't dwell on this too much, it's not healthy."
That was why he was friends with her. He'd feel so much better right now if he didn't know, deep down, that he wasn't dwelling on the action itself; he was dwelling on his lack of remorse over it, on the man he was changing into.