Winston Marshall had to leave Mumford and Sons to be able to stand up for himself. For anyone willing to throw away a life's worth of investment into their career in order to speak their mind, that's a good piece of advice. For everyone else, apologize.
Or better yet, avoid getting into hot water. I have found HN to be a great barometer for what's "acceptable" and what isn't. Recently, I learned a valuable lesson - I shared an accurate statement about FB's targeting precision, which I am pretty sure nobody would have objected to. But as soon as I tied it to their financial results, it instantly offended one person and others felt they had to jump in as well.
Lesson learned: the fact that Facebook is printing money is such a thorn in the eye for many people that the minute it's brought up in an unrelated context, it will 1) derail the conversation, 2) get people to disagree with what would have otherwise been a straight forward argument, and 3) get people to vilify you.
So now that we know about this thorn, we can not just avoid it in future conversations, but we can also leverage it to our benefit. For instance, all you have to say is: "Man, I wish we could somehow get Facebook banned. Here's how effective their targeting is..." - and voila, everyone is agreeing with you!
Long story short - don't piss against the wind.