The Iran hostage crisis ushered in an era in which the greatest foreign policy challenges
facing the United States were the threats posed by conflicts in the Middle East. Today, the United States still finds itself facing similar threats in this region. The wars in Iraq and Afghanistan, diplomatic struggles with Iran, and the ongoing threat
of terrorism continue to create problems for the United States.
The main focus city of the Crusades was Jerusalem. The idea was that it was Christian territory, or at least should be Christian territory, and they always went to reconquer it. The fourth Crusade never made it to Jerusalem because they were busy sacking Constantinople which had a lot of troubles due to constant wars of the Byzantine Empire.