The revolution brought immediate confrontation.
One of the most dramatic moments came when Iranian students stormed the U.S. Embassy in Tehran, taking American diplomats hostage for more than a year.
For Washington, it was a humiliation.
For Tehran, it was a symbol of resistance.
Diplomatic relations were severed.
Iran's nuclear projects slowed down after the revolution, partly because many Western partners withdrew their support.
Yet inside Iran, leaders continued to believe that nuclear technology represented independence and strategic strength.
Meanwhile, Israel began watching Iran with growing concern.
For Israeli leaders, the possibility of a powerful regional rival developing nuclear capabilities was a serious strategic threat.
The seeds of suspicion had been planted.