The US intervention in Iran in the 1950s led to the Islamic revolution of 1979. In 1953, the United States and the United Kingdom orchestrated the overthrow of the democratically elected Prime Minister Mohammad Mosaddegh in favor of the monarchical rule of Mohammad Reza Pahlavi, also known as the Shah. The Shah imposed a lot of secular transitions in Iranian society in the following years, which were opposed by Islamist organizations. Ultimately, this would lead to the Islamic revolution of 1979, during which the Shah monarchy was overthrown and the Islamic Republic under the Grand Ayatollah Khomeini was established.
The intervention did not inspire future democratic elections. The Shah was accused of violating the Iranian constitution, political corruption, and political oppression.
Nor did the intervention led to US support of Iranian nationalists, since all republicanist political dissent, including the nationalist opposition, was suppressed.
And the intervention was actively supported by the British government and thus not opposed.
