What's hot on Google+

Why does Google+ feel the need to send me "what's hot" posts from those outside my circles? Many of these posts seem intended to start a political argument. One reason I do not spend much time on Facebook is that I do not want to engage with my relatives on political issues when these individuals seem to have very different values from my own. I am certainly willing to engage in discussion with those who seem to understand argumentation, but how does one find partners for an approach that will not disintegrate into vulgarities as a means of interaction? Social media has never been very successful when it comes to establishing guidelines for productive interaction.