Why are Iran and Israel sworn enemies?

Once allies, Iran and Israel’s relationship deteriorated after Iran’s 1979 Islamic Revolution, with Ayatollah Khomeini severing ties and criticizing Israel’s occupation of Palestinian territories. Despite some Iranians questioning this hostility, the current leadership, including Ayatollah Ali Khamenei, maintains an antagonistic stance, even denying the Holocaust. Some supporters of the Islamic Republic criticize Iran’s reluctance to directly confront Israel.