A progressive, democratic Iran would have been such a better ally for the United States over the past seventy years than the Saudis (or even the Israelis) have been. But instead, we made them an enemy by toppling their democratic government. We really need to stop manufacturing enemies for the next war.
US is literally the reason there are no progressive and democratic governments in the Middle East. The reason being that actually democratic governments work in the interest of their people as opposed to the interests of the empire. US overthrew a progressive and democratic government in Iran was because they nationalized their oil. What the empire actually cares about is extracting labour and resources from the rest of the world.
Mistakes, for whom? The MIC made out like bandits.