I wholeheartedly agree with your sentiment. I'm not even sure how to approach such a misguided argument. So I haven't yet, because I didn't want to lower the level of conversation on hn.
I simply meant to encourage you to avoid snarky one-liners like one you've posted, and instead raise the level of discussion here.
Some things that I disagree with are great for intelligent discussion. Other things I'd discourage regardless of the intelligence or sincerity involved.
An adult should know what is wrong with setting landmines. See: http://www.globalissues.org/article/79/landmines We should say this firmly.