Iran (real name Persia) has always been seen as a bit of a threat to the rest of the world. The country’s alliance with the Russians in the late 1830s led directly to the siege of Herat, where Eldred Pottinger spent the best part of a year helping to defend the city.
Worse than that, the Persian-Russian threat was considered so serious the British invaded Afghanistan to protect the frontier of India.
None of it turned out well: it’s all in ‘The Trials of Eldred Pottinger’.