That, of course, is not the same as saying it's a perfect deal. No agreement would have been. Whether the U.S. could have gotten an even better deal if it had been willing to hold out longer in Vienna, as Mr. Netanyahu insisted, is ultimately unknowable.On the other hand, the consequences of Congress rejecting the deal Mr. Kerry negotiated are all too easy to imagine. It would almost certainly wreck the international sanctions regime imposed on Iran because other countries would be unlikely to follow the United States' lead and instead would lift their sanctions unilaterally. That not only would weaken the most important leverage the U.S. has to restrain Iran's nuclear program, but by releasing billions of dollars into its accounts, it would also put Iran back on a path to a bomb in a greatly strengthened position. That's in neither our interest nor those of our allies in the region.