I've noticed anti-American rhetoric on IPS several times, mostly in the form of comments.
For example, in this question
How to tell a co-worker that I feel sorry for something I did?
Jess's answer got these comments:
Just chiming in to say not being able to say 'Sorry' after a car accident is a very American thing. 'Sorry' means different things in different countries. – Rob 2 hours ago
and
Yeah only the US will try to sue someone for saying sorry. Even if something is not your fault, it is polite to apologize to show empathy. This applies to both car accidents, and OP's situation. – Edmund Reed 2 hours ago
Both are blanket statements that try and portray Americans as incapable of apologizing or showing empathy. If the IPS SE community doesn't (currently) have a great deal of American participants, then these negative comments could stay on for quite a while, because nobody would flag them.
And, if we anticipate IPS to grow, new American users would likely be put off by such comments that are seemingly tolerated (by a predominantly non-American userbase, perhaps).
Should moderators remove these comments rather than wait for people to flag them?