1: 1. Afghanistan: Conflict and terrorism make it unsafe for Americans. 2. Iran: Strict laws and political tensions pose risks for travelers.

2: 3. North Korea: Closed-off dictatorship with high risk of arrest. 4. Venezuela: Economic crisis leads to high crime rates and unrest.

3: 5. Yemen: Ongoing civil war and limited access to basic services. 6. Syria: Conflict and instability create dangerous conditions for tourists.

4: 7. Iraq: Continued violence and terrorism make it unsafe for Americans. 8. Libya: Political instability and conflict result in unsafe environment.

5: 9. Somalia: Civil war, piracy, and terrorism pose threats to travelers. 10. South Sudan: Conflict and humanitarian crisis make it a dangerous destination.

6: 11. Central African Republic: High crime rates and political unrest prevail. 12. Democratic Republic of the Congo: Ongoing conflict and violence pose risks.

7: 13. Honduras: High levels of violence and crime make it unsafe. 14. Guatemala: Gang violence and political instability create risks for travelers.

8: 15. El Salvador: Gang violence and crime rates are dangerously high. 16. Brazil: Violent crime and political unrest affect safety for tourists.

9: 17. Mexico: Drug cartel violence and crime pose risks for travelers. 18. Nigeria: Terrorism, kidnapping, and unrest make it unsafe for Americans.