when ur part of a "society" as the losties were, the overall vote was NOT 2 kill ethan. 4 all we kno ethan could of been torched by sayid n confessed up to all of the other's plans and whereabout (prob. not cuz the others seem super loyal) but we will neva know now, cuz charlie killed him.

i do understand y he killed i mean he kidnapped him n claire, n lenched him, but still he acted without thinking...

It was a weak decision from the writers actually, and as far as I know, the weakest link in the LOST story.

It was obvious they killed him off because they wanted to keep "The Others" till Season 2, and killing him off "to protect Claire" didn't affect me or made me feel he was any hero. Instead, he bothered me a lot.

It is the only situation in my opinion where the LOST writers had to give secrecy a bigger importance then real logical events, meaning, they were more concerned about keeping the Others secret until later seasons, than actually making a sense in killing him.

killing ethan makes very good sense to me. and not because i like charlie so much. even if kate, my least fave character, did it i'd still support her decision. when you've crashed on an island and you've known these people for only a few weeks you usually follow your judgement and not everyone else's. i dont think the losties had the time to become a "society" by then. im not so sure they ever had the time to become one having only 108 days together.
the only one charlie really cared about was claire and of course himself. which sounds pretty logical...at least to me. ethan hurt both claire and charlie. needless to say he kidnapped claire and left charlie for dead.
i think his reason was more than just taking revenge. who could be really certain that if they let ethan live he wouldnt just escape and threaten them all over again? or that ethan's people( they didnt know them as "others" yet) wouldnt attack the camp to take him back? they didnt have the hatch or the armory back then. all they had was tents. not really a suitable place to keep a prisoner. and especially a prisoner like ethan.
finally, as i said before, charlie only knew the others for a few weeks. what if jack assured him ethan wouldnt hurt anyone anymore? charlie didnt know for sure. the only thing he knew was that if he wanted to be protected he could only trust himself.
sure as a viewer and an addict i was devastated not being able to know more about ethan then and there but as far as logic goes i think charlie is justified.

anyway. sorry for writing such a long post. :)

He overreacted, but had good reason to do so. if someone kidnapped your girlfriend and hung you up to die, and you were on a strange island, you probably would have too.