Nonetheless, weaknesses in its terms, structure, implementation and basic strategic fallacy - i.e., that Iran's international behavior would "moderate" once it was adopted - are all increasingly apparent. For the deal's acolytes, however, continuing U.S. adherence has become a near-theological imperative.
At the most basic level, the agreement's adherents ignore how ambiguous and badly worded it is, allowing Iran enormous latitude to continue advancing its nuclear-weapons and ballistic-missile programs without being even "technically" in violation.
The adherents ignore Iran's actual violations (exceeding limits on uranium enrichment, heavy-water production and advanced-centrifuge capacity, among others). Having first argued strenuously there were no violations, they now plead that the violations are "not significant."
The adherents ignore the "truth-that-dare-not-speak-its-name": America does not know with confidence where all of Tehran's nuclear and missile work is being done.
Unfortunately, both the International Atomic Energy Agency (IAEA) and our national intelligence assets are likely missing significant Iranian facilities (perhaps operated jointly in North Korea) that continue to pursue threatening activities.
The adherents ignore statements by Iran's leaders (always worth taking with many grains of salt, to be sure) that Iran could restart full uranium enrichment within five days of discarding the deal's limitations; that reconstructing the Arak nuclear reactor, intended as a plutonium production facility, is easily done because the required "disabling" steps turn out to be not so disabling; and more.
The fact is that Iran's negotiating "concessions" were always trivial and easily reversible.
The adherents ignore Iran's ongoing belligerent behavior in the Middle East, including constructing an Iranian "arc of control" once ISIS is defeated in Iraq and Syria, giving Tehran's military forces a strategic highway from Iran through Shia-dominated Iraq, into Assad's Syria and then Hezbollah-dominated Lebanon. Israel and our Arab friends clearly see this danger.
The adherents ignore Iran's continued efforts to threaten and harass U.S. forces deployed in the Persian Gulf region, even as we wrongly pursue Obama's strategy to empower Baghdad's Tehran-dominated government in the war against ISIS.
Such blindness is not a strategic option. The Obama agreement's geopolitical errors, its conceptual fallacies, its textual weaknesses and its operational dangers are now all too palpable. This is a time for action, not equivocation.
Heedless to reality, however, deal supporters are now reduced to a maladroit ploy. The White House, they say, should refuse to certify next month under the Corker-Cardin legislation that the pact is "vital to the national security interests of the United States."
However, rather than acknowledging candidly that an agreement contrary to our interests should be abrogated, they urge the administration to "fix" problems they spent years denying even existed.
President Trump should reject this "one-shoe-on, one-shoe-off" approach. It is unbecoming and unpresidential at best, dangerously confusing at worst, since it fails to address squarely the risks inherent in allowing the Obama deal's rapidly crumbling legitimacy to retain any force or effect.
Staying in a bad agreement sends confusing signals to the Europeans, who are confused enough already on this issue, about how America intends to address the Iran threat. Similarly, it shows weakness and indecisiveness to Russia and China at precisely the point when President Trump should project clear-eyed resolve.
While some say we should first deal with North Korea's more imminent threat, postponing action on Iran, so doing ignores the inextricable relationship between the two, both operationally and in global perceptions.
Just as misguided is the idea that, by not certifying, President Trump could hand over the Iran deal's fate to Congress. The Constitution's framers would be appalled by such a notion. Decisive presidents do not wittingly cede their constitutional responsibility to Congress, particularly when existential questions of national security are at stake.
As Alexander Hamilton wrote in Federalist Number 70, only the Executive possesses the "decision, activity, secrecy and dispatch" necessary to make critical foreign-policy choices. And Senate Democrats would prove Hamilton right by filibustering any effort to gut the deal legislatively.
Deal advocates next argue we should "strictly enforce" its provisions, but this is delusional. The deal is poorly negotiated and vaguely worded. For example, Obama failed to demand baseline inspection of the Iran program's military dimensions before inking the deal, and the IAEA is now routinely denied access to regime military facilities.
Trying belatedly to "strictly enforce" such a deal is like trying to nail jelly to a wall. The saying that "Iran has never won a war, and never lost a negotiation" surely applies with full force here.
Nor is it possible to "fix" the deal. A conceivably acceptable Iran agreement would require truly intrusive international inspections, as far as imaginable from those permitted under Obama's deal. Iran (like North Korea or any authoritarian society) could simply not accept the kind of international presence required to prove compliance. So doing would undermine the regime itself. Fixing the deal is out of the question.
The president need not wait until October, when his presidency's third Corker-Cardin certification decision is due. As required every 120 days, he must decide this week whether to continue waiving oil- and banking-related sanctions suspended under the Iran deal. Trump granted such a waiver in May, but he should not do so again.
September brings us two telling anniversaries. One, the tragedy of 9/11, reminds us what happens when America lets down its guard, even inadvertently, to international threats. The other, Sep. 6, marked the 10th anniversary of Israel's successful strike against a nuclear reactor in Syria being built by North Koreans, quite possibly with Iranian financing.
A deliverable nuclear-weapons capability in the hands of Tehran's ayatollahs and the Revolutionary Guards, religious extremists supported by a fascist military, could make another 9/11 far deadlier than the first. This is not the time to light candles to Obama's Iran nuclear deal, but to snuff them out.
John R. Bolton served as U.S. ambassador to the United Nations and as undersecretary of State for arms control and international security affairs at the U.S. Department of State under President George W. Bush.