In the context of Hacker News, disagreement is welcomed (in a way even encouraged) as long as it is constructional and argumentative.
Again, depends on what the community accepts and wants. I agree politically sensitive topics are turmoil, but it doesn't take much for a community to be accepting of different views.
If the goal is to feed intellectual curiosity, another way of seeing things is always welcomed as long as it is written well
It only gets more interesting with each day :)