From Today in Alternate History, inspired by Let's Talk About History
On this day Mohammad Reza Pahlavi the Shah of Iran fled Iran with his family and relocated to Egypt. Political unrest had transformed the country into a revolution and shortly thereafter, the monarchy was formally abolished, and Iran was declared an Islamic republic led by Ayatollah Khomeini.
Having so recently saved Vietnam from Communism, it was a disastrous turn of events for Richard Nixon during what should have been his "victory lap" third term. His Government had been fully committed to the "Twin Pillar" cold-war strategy of supporting Saudi Arabia and Iran in order to control oil supplies in the Middle East. And during his first year as Eisenhower's Vice President, the Iranian oil industry was briefly nationalized under the democratically elected Prime Minister Mohammad Mosaddegh before a US-backed coup d'état deposed Mosaddegh and brought back foreign oil firms.
As a result of this long standing personal entanglement the downward spiral of crisis continued to escalate across the whole region drawing Nixon into the picture as a Satanic bogeyman. Because the Arab masses were enraged that the Shah, a hated autocrat, had arrived in their country with an entourage, acting as if he was still Head of State in Exile and hoping that the US Government would restore him to power after a brief interruption to 2,500 years of continuous monarchy since the founding of the Persian Empire by Cyrus the Great.
With the Egyptian Government quickly losing control of events, Nixon readily agreed to provide sanctuary for the Shah at the American Embassy in Cairo whilst he could arrange some form of extraction. But this secret movement was betrayed, and protesters assembled outside the Embassy Gates, shouting revolutionary slogans. The Iranian Revolutionary Government demanded the return of the Shah to Iran to stand trial for his crimes. When Nixon refused the Embassy was overrun by militants and the whole Temple began to topple.