In 1748, as part of the Treaty of Aix-la-Chapelle, France regained Cape Breton from Great Britain. The island, off the coast of Nova Scotia, had passed back and forth between the two countries over the years, and previous treaties had been as binding as toilet paper. But as part of the 1748 treaty, Great Britain sent several British peers to Paris as a guarantee of the British kings good faith in the latest agreement.

The transfer of Cape Breton was a rather insignificant provision of a largely forgotten treaty. But the implementation of the treaty was hugely important.

The dispatch of the British peers was the last incidence of an ancient and once-common tradition: the use of hostages as part of the negotiating process. If the British reneged on their promises, the French could simply throw the peers into chains (or worse), much as their Roman predecessors had turned well-treated hostages into prisoners of war in the case of non-compliance. After 1748, however, countries would no longer put the bodies of their citizens on the line in the service of international diplomacy.

The problem of trust continues to bedevil diplomatic negotiations. For instance, can one side trust the other to keep their discussions confidential, and, later, can the negotiators trust that the offers on the table are genuine? If, through a long and usually tedious process, the negotiators manage to establish some measure of trust in one another, an agreement may ensue. Then the issue becomes whether the signatories will abide by their promises. Trust, but verify, Ronald Reagan famously said about the Soviets and arms control treaties.

But theres an equally challenging issue of trust involved in the sale of the agreement. The negotiating parties must ask their constituencies at home to trust that the deal, which is nothing but words on paper, will translate into concrete results. Hostages are no longer a guarantee of implementation. Instead, diplomats today can only offer more words.

In effect, they have to promise that promises will be kept.

And so it was with the Obama administration last July when it had to sell the nuclear deal with Iran to both Congress and the American people. It was not as if Iran sent a couple of high-ranking clerics to Washington, DC as surety for the deal. Nor could the United States point to anything specific that Iran did as an immediate result of signing the agreement. Everything was a promise: to dismantle 13,000 centrifuges, cap the enriching of uranium at low levels, and ship nearly 10,000 kilos of the radioactive material out of the country. If and only if Iran fulfilled these promises, the United States would lift nuclear-related sanctions and release tens of billions of dollars in frozen assets.

After a strenuous campaign by both the administration and civil society organizations in support of the nuclear deal, it squeaked through Congress despite the opposition of the Republican Party and a few renegade Democrats . Then came the waiting.

The administration was heavily invested in the deal as an example of how its kind of diplomacy could resolve problems that others (congressional hawks, Israeli Prime Minister Benjamin Netanyahu) would have used military means to address. Essentially, the administration was gambling that Iran stood to gain much by the agreement and lose even more by reneging on it. Moreover, President Obama and Secretary of State John Kerry were betting that their counterparts in Iran could effectively handle their hardliners with the promise that the United States would keep to its side of the bargain.

Finally, last week, both sides kept their promises. On Implementation Day, Iran fulfilled its obligations under the agreement and the United States lifted non-nuclear sanctions. You might say that the Obama administration won the diplomatic equivalent of Powerball and it looks as though the Rouhani administration in Iran chose the same numbers as well. The two lucky ticketholders will share the geopolitical jackpot (and who knows: maybe the payout will also include the next Nobel Peace Prize).

The first dividend checks arrived this week. As in 1748, they came in the form of bodies in motion. But this time it wasnt hostages heading over as guarantors but, rather, sailors and prisoners released to their relieved families.

Parallel Negotiations

During the heyday of dtente in the 1970s, the United States and Soviet Union negotiated a number of arms control treaties. Not everyone was thrilled with these diplomatic victories.

What would later become the neoconservative movement, initially a group of Cold War hawks who rallied around Democratic senator Henry Scoop Jackson, objected to the failure of the Nixon administration to link human rights to its arms control initiatives. The objection wasnt entirely fair the Helsinki Accords, for instance, brought together human rights and security issues within the same framework. But the notion was born that negotiations with an adversary on only one narrow set of questions were somehow illegitimate.

The opponents of the nuclear deal with Iran certainly had their beefs with the substance of the agreement. But they also castigated the Obama administration for not addressing a range of non-nuclear issues, such as Irans missile program, its human rights records, its support of non-state actors like Hezbollah, and the very form of its government.

One of the more controversial attacks, however, concerned the handful of Americans that Iran had arrested, tried, and jailed, including Washington Post journalist Jason Rezaian. As prominent deal critic Tom Cotton (R-AR) wrote in October :

The immediate release of Jason Rezaian and the three other American hostages should have been a precondition of any deal reached with Iran. Instead, President Obama prioritized reaching a deal for his own legacy over the health and safety of American citizens. The Iran nuclear deal put all our chips on the table in exchange for nothing. I fear Iran has little incentive to allow the release of Jason and his fellow hostages.

The Obama administration did not, however, abandon Rezaian and the others. As Robin Wright writes in The New Yorker , the administration opened up a second track of diplomacy alongside the nuclear negotiations to address the fate of the Americans locked up in Iran. The two initiatives were both linked and unlinked. This second discussion was made possible by the contacts already made on the nuclear issue. And yet, as Wright explains, they proceeded separately:

More than a year of informal discussions between [Wendy] Sherman and her counterpart, Majid Takht Ravanchi, the Iranian Foreign Ministry official in charge of American and European affairs, led to an agreement, in late 2014, that the issue should be handled separately but officially through a second channel. After debate within the administration, Obama approved the initiative. But it was so tightly held that most of the American team engaged in tortuous negotiations on Irans nuclear program were not told about it.

It was one thing for the deals critics to call into question the administrations supposed insensitivity. They didnt, after all, know anything about the secret negotiations. (And it wouldnt have been the first time that administration critics talked authoritatively about something they knew nothing about.)

But it beggared the imagination that they would continue to criticize the administration afterthe release of the captives. Heres Cotton again :

But in our elation over their safe return we must be careful not to forget the dangerous circumstances of their release. President Obama has appeased Irans terror-sponsoring ayatollahs, this time with a prisoner swap to secure the overdue release of four innocent American hostages in return for which Iran gets seven lawfully convicted terrorists and criminals, fourteen terrorism prosecutions halted, $100 billion in sanctions relief, and an industrial-scale nuclear program and Iran gets to keep Americans Siamak Namazi and Robert Levinson to extract future concessions. While we exult in the return of American hostages, one must also wonder how many more Americans will be taken hostage in the future as a result of President Obamas shameful decision to negotiate with these terrorists.

Say what?

The notion that Iran somehow got a better deal because it received seven detainees and the United States received only four is a criticism you might expect from a second-grader proud to show off newly learned arithmetic skills. How would Cotton have evaluated Israels exchange of over 1,000 Palestinian prisoners for one soldier, Gilad Shalit?

As for Cottons other assertions, they dont even pass the acuity level of the average elementary school student. Iran gets sanctions relief worth at most $50 billion, not $100 billion for the nuclear agreement. not the prisoner swap. And the agreement halts Irans nuclear program, not maintains it.

As for future hostages, Iran had a chance to hold on to 10 sailors whose boats had not only entered the countrys territorial waters last week, but also navigated close to a sensitive military installation. Contrary to initial reports , the boats were not in mechanical distress at the time of the mishap. And what did the nefarious Iranians do? Demand the lifting of more sanctions or the release of other Iranians in captivity?

No, Iran sent home the sailors within 24 hours without anything required in exchange.

Cotton wasnt the only person to make asinine comments. Donald Trump , in his inimitable way, argued that the releases should have taken place three-and-a-half years ago before some of the detainees had even been seized. Then he tried to claim responsibility for the release because of his unrelenting anti-Iranian rhetoric. Ive been hitting them hard, and I think I mightve had something to do with it, he said .

If Iran has been paying any attention to Trump at all, I suspect that they are doing so for comic relief or, like Britain, to debate whether to ever let him into the country.

The Winning Ticket

The future dividends from the nuclear deals payout are not entirely clear.

For Iran, the infusion of foreign capital about $70 billion altogether, estimates economist Djavad Salehi-Isfahani should lift the economy out of recession. But various structural impediments in the economy will restrict growth to a relatively modest 4-5 percent next year. Elections to the parliament and council of guardians are coming up at the end of next month, and conservatives are hoping to game the results by disqualifying as many reformers as possible before the candidate lists are finalized.

But even if the conservatives manage to block the reformers in the short term, the eventual turnaround of the Iranian economy will ultimately give an enormous boost to the larger political and economic agenda of the comparatively moderate president Hassan Rouhani. For those bent on regime change in Iran or the hobbling of its regional ambitions, the strengthening of the Rouhani faction is probably bad news. It means that a more open and flexible Iran, under its current system, will play an expanded role in the Middle East and globally. Thats not something that Saudi Arabia, Israel, the Islamic State, or Tom Cotton wants to see. But its a welcome development for most everyone else.

For the Obama administration, meanwhile, the successful implementation of the Iran deal represents an important victory for statecraft. It puts the critics of the administration on the defensive, struggling to come up with an alternative that produces something other than rhetorical effects. Some of the more ambitious members of the administration hope that the deal will provide regional dividends in the form of better prospects for a peace agreement in Syria, diminished hostility between Tehran and Riyadh, a united front against the Islamic State, reduced scope of activity for Iranian proxies such as Hezbollah, and greater chances for stability in Iraq.

Its too soon to tell whether the Powerball winners will be able to enjoy these particular dividend checks. They should also be aware that many top lottery winners suffer fromsudden wealth syndrome, which consists of financial mismanagement, thwarted hopes, and social isolation. Both winners should take care to husband their new political capital against the inevitable backlash.

During this brief interregnum between exalted expectations and dreary realism, lets celebrate once again that rarest of things: good news in a perilous world.

Crossposted with Foreign Policy In Focus