Generalization is a bad habit
We tend to group and categorize people of certain cultures, race, creed and the nation of which they may reside and form in our minds the opinion that they must all act and think alike.
This rush to judgment can cause resentment and/or animosity among those being profiled. It is especially dangerous to lump all individuals of a given nation to the concepts of their rulers.
For instance: Is it unfair to say that everyone with a tattoo must belong to some ominous motorcycle gang? Nor is it fair to assume anyone wearing a Muslim-type headdress belongs to a cult.
To make a generalized statement that all Iranians are enemies of the United States is simply false and misleading. On the contrary, the vast majority likes Americans.
We all must break the habit of generalizing and learn to be more pacifistic, straightforward and careful in our dialogue.