A new study has found that both friends and foes can create national unity, but in different ways. Friends create unity by fostering positive emotions and feelings of trust and cooperation, while foes create unity by generating negative emotions and a sense of shared threat.

The study, published in the journal "Political Psychology," analyzed data from the European Social Survey, which measures public opinion in over 30 European countries. The researchers found that countries with high levels of friendship also had high levels of national unity, while countries with high levels of enmity also had high levels of national unity.

However, the researchers also found that the type of unity created by friends and foes was different. Friends create what the researchers call "positive unity," which is characterized by trust, cooperation, and a sense of belonging. Foes, on the other hand, create what the researchers call "negative unity," which is characterized by fear, anger, and a sense of grievance.

The researchers argue that both positive and negative unity can be beneficial for a nation. Positive unity can help to foster a sense of community and cooperation, while negative unity can help to mobilize people in times of crisis. However, the researchers also caution that negative unity can be dangerous if it becomes too intense or is used to justify violence or discrimination.

The study's findings have implications for understanding the role of friendship and enmity in politics. Friendship can be a powerful force for good, but it is important to avoid letting it become exclusive or to allow it to turn into enmity. Similarly, enmity can be a motivating force, but it is important to keep it in check and to avoid letting it lead to violence or discrimination.

Positive Unity - Trust, cooperation, and a sense of belonging.

Negative Unity - Fear, anger, and a sense of grievance.