Nothing wrong with a company not wanting lost productivity due to non work-related activity.<p>It seems reasonable to have a rule that says "don't get into arguments or spend significant work time on non work-related topics"<p>If people are violating that standard predominantly with political topics, then make the rule explicit and specific.<p>People should be professional enough to do this on their own, but many aren't, and an explicit rule makes sure you don't have a constant parade of disruptions and firing employees because they're not doing their work or stopping others from doing theirs.