The word "resentment" has become unavoidable in discussions of modern violence, especially when trying to understand why some young men—often white, often isolated—transform grievance into destruction. The Anger Rumination Scale measures this "stewing" style, which predicts both internalizing issues like anxiety and depression, and externalizing behaviors, including aggression. The pattern is clear: stewing leads to more intense and persistent anger, causing emotional spillover into other areas of life. Feeling diminished—either personally or as a group—can turn a fleeting anger into a lasting, meaningful grievance. Studies show that people who score high on anger rumination measures are more likely to engage in both verbal and physical aggression when provoked.