Many analysts attributed Iran’s current economic crisis, the initial cause of the widespread protests in the country, to the weight of those sanctions.
Sanctions tighten the economy. Economic tightening leads to misery. Misery leads to social upheaval. Upheaval leads to violence. Violence becomes a justification for more sanctions.
But hey, Iranian-style Islam is ontologically evil. Just gotta keep squeezing until we can depose the Guardian Council and replace it with... checks notes... a military dictatorship backed by the Saudi Wahhabists?