Rand Paul announced his opposition to the nuclear deal with Iran earlier today:

The deal is bad because 1) sanctions relief precedes evidence of compliance 2) Iran is left with significant nuclear capacity 2/2

— Dr. Rand Paul (@RandPaul) July 14, 2015

These are terrible reasons to oppose the deal. There was bound to be some sanctions relief up front to give Iran’s negotiators something that they could sell to their people back home and to give them an incentive to follow through with their side of the agreement. Paul’s objection is flawed because he assumes that a “good” deal would require Iran to fulfill all of its obligations before it gained anything from the agreement. If the deal had been structured this way, there probably wouldn’t have been an agreement. More to the point, sanctions relief is what the U.S. and the other members of the P5+1 are expected to offer as their part of the bargain. If these governments didn’t offer any sanctions relief at the start, they would be failing to comply with their commitments. In short, Paul is opposed to the deal because it includes a compromise that was probably necessary in order to secure an agreement that achieves a much more important goal. That’s no reason to oppose the result of a successful negotiation, and it suggests that Paul wants to continue his vain efforts to placate his party’s hard-liners.

The second part of this objection is even worse than the first because it was always certain to be part of any deal. Iran was always going to retain some significant “nuclear capacity” so long as its nuclear program remained intact, and it was never going to negotiate away its entire program. Faulting the deal for “leaving” Iran with a much more restricted program than it had before negotiations started is the definition of making the perfect the enemy of the good. It is an extremely unreasonable position, and one that continues his self-defeating pattern of increasingly hawkish posturing.

Paul’s chance at the 2016 nomination was never that great, but to the extent that he had a chance it required him to distinguish himself from the rest of the field and to offer the party a clear alternative to the party’s current foreign policy. He has spent the last year and more going out of his way to eliminate the things that distinguished him from his competitors, and he has repeatedly embraced positions on foreign policy that make him little more than a conventional hawkish Republican. He has won no new supporters in the process, but he has guaranteed that what little support he still has will keep evaporating.