Comments by "annoyed aussie" (@annoyedaussie3942) on "Iran election: Hardliner Raisi sweeps to victory amid low turnout | DW News" video.

In one word , history. The US is one of those countries that tends to hold a grudge for a long time and has a long memory. Cuba is the prime example of this, no threat to anyone outside of Cuba but still significant sanctions, compare to Vietnam , while slow they only took 20 years approximately to normalize relations. I am Australian and although it's nowhere near the force of sanctions China has decided to effectively put some limited trade sanctions on Australia, a former Prime Minister has suggested they might last a long time.
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@mohamedsaid9416 Sanctions can be from the UN security council and for unilateral sanctions by the US it could go through Congress (personally think it always should) however in recent years US presidents seem to just do it themselves and even if it goes through Congress the president has veto power so the final decision will always be the president in the case of US unilateral sanctions.
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