Iran and Syria are completely different from one another in terms of Freedom of Religion. Iran is a country with a state religion of Shia Islam which is not only against Non-Muslims but also against Sunni Muslims.
Syria on the other hand is a secular country with no state religion and complete freedom to practice religion.
Syria is more similar to the United States in providing more freedome of religion, while Iran does not provide freedom to people of Sunni Islam or Bahai' faith.