Please explain why it's okay for the US to have nuclear weapons but not for Iran to have them?

Please don't tell me that somehow it's because Iran is less trustworthy. The U. S. has an abundance of nuclear weapons and delivery systems and is the only country that has ever used them, which it did in 1945 against two different civilian cities killing many hundreds of thousands of people. Somehow people argue that the U. S. is more trustworthy? Particularly with a lunatic like Trump in charge?

Please explain how the U. S. is more trustworthy and Iran is less trustworthy.

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3 mo
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Please explain why it's okay for the US to have nuclear weapons but not for Iran to have them?
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