Two things can be true, and are both true, both at the same time:
1. The current Iranian regime rules with an iron fist and murders 10.000++ of their own citizens.
2. US military intervention against current Iranian regime will only result in further humanitarian tragedy, won't bring about regional peace.
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As many have pointed out, moreso most recently, look at how US spent decades, trillions of dollars, and thousands of US soldiers' & Afghani civilian & govt lives to "successfully" replace the Taliban with the Taliban.
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