Paul Pillar reminds us that the nuclear deal with Iran cost the U.S. nothing:

The concessions the United States made to Iran in the recent negotiations did not involve giving up anything that represents any losses or increased vulnerabilities or added potential for harm to our interests. Besides dealing with the pace of the sanctions that have value only insofar as they get a deal, the concessions were all about just how much the Iranians would be giving up in the way of restrictions on, and scrutiny of, their own nuclear operations. And the baseline for that—equivalent to the state of affairs before the negotiations began, and what would prevail if the deal is killed—was no restrictions or scrutiny at all beyond the minimum to which Iran was subject as a party to the Nuclear Nonproliferation Treaty. Everything that the United States and P5+1 got beyond that is pure gravy for our side.

In short, the deal was an extremely lopsided one in favor of the P5+1. According to the deal, Iran will receive some sanctions relief in exchange for accepting major restrictions on its nuclear program that the NPT does not require it to accept. To the extent that the P5+1 actually conceded anything, they gave up on a maximalist demand (zero enrichment) that was both unobtainable and irrelevant for the purposes of preventing Iran from acquiring a nuclear weapon. If the U.S. and its European allies had been willing to compromise on this point ten years ago, it is likely that an even better deal could have been struck at that time that would have left Iran with a much less advanced nuclear program than the one it will be allowed to keep as part of this deal. Using sanctions to try to compel Iran to give up everything was a failure on its own terms, and in the end the U.S. and the other world powers settled for a compromise they probably could have had a decade ago.

Insisting on maximalist goals did nothing to limit Iran’s nuclear program, and it was only by giving up on those goals that the negotiators were able to reach an agreement that established significant limits on and monitoring of that program. All that the U.S. has to give up to achieve this is some of the punitive measures that it has imposed on Iran. This does no harm to the U.S. or its allies. The deal also reduces the chance of a conflict with Iran, which would have many of its own serious costs and risks that the U.S. is now better able to avoid. It’s a great success for the U.S. and further confirmation that hard-line policies offer nothing but failure and dead ends.