I'm sure you've at least heard what the United States' leaders have to say. To paraphrase Trump, "stopping nuclear proliferation to a group of lunatics that support terrorism". And also (still paraphrasing Trump), "the US doesn't need this as much as the rest of the world." So, perhaps this doesn't put the US ahead relative to other countries, but it puts them ahead of the counterfactual nuclear wasteland they could become.

Whether or not you believe the United States' leaders, whether or not you think there was a better way for them to achieve their goals (something something Obama deal) is up for debate. But it's very facetious to say you "can't think of a single way in which the United States came out ahead in the war," when the United States' leaders have been publicly announcing it for nearly a year.