British Foreign Secretary Boris Johnson said hopefully that "sometimes the hour is darkest before dawn" and there was "space to compromise." But equally it might just be midnight.
US Secretary of State John Kerry -- sitting opposite his Russian counterpart Sergei Lavrov at the UN Wednesday -- said he had "profound doubt whether Russia and the Assad regime can or will live up to" the cessation agreed just twelve days previously.
The utter absence of trust within Syria is now replicated beyond, in the relationship between the US and Russia and among other players and their proxies.
Turkey, Saudi Arabia, Qatar and Iran -- who all have skin in the Syrian game -- were not involved in negotiating the ceasefire, nor in its unraveling. They paid lip-service to the agreement but continue to pursue their own agendas in Syria. Sometimes their interests coincide with those of the "great powers." Increasingly they don't and they're not afraid to show it.
All about red lines
The Emir of Qatar went public with his frustration at US hesitancy in Syria. Sheikh Tamim bin Hamad al-Thani told the UN General Assembly that "red lines were set for the regime, which has violated them."
Assad "became aware of the fact that there is no ceiling for what it could perpetrate without accountability," he added.
Qatar's views matter because it provides millions in cash as well as a supply line of weapons, to its favored groups in Syria.
The same exasperation is felt -- but expressed privately -- in Saudi Arabia.
Turkey supported the US-Russian deal, but did not expect it to last. And anyway it has other priorities. The main one is to confront and contain the Syrian Kurds, who hold a big chunk of northern Syria. Turkish officials have frequently criticized the Obama administration for supporting the Kurds as their battering ram against ISIS.
Now, according to President Recep Tayyip Erdogan, Turkey and its allies among Syrian rebels could end up taking 5,000 square kilometers of territory in northern Syria. That would lead to further clashes with the Kurds, just as the US looks to bolster them ahead of the campaign to kick ISIS out of Raqqa -- its self-declared capital.
Iran -- whose militia have fought alongside the Syrian army -- was suspicious of the deal agreed in Geneva on September 10. Vice President Ishaq Jahangiri claimed the US "abuses ceasefires" to "buy time for terrorists to reinforce and reorganize." But the Iranians went along with the deal because it proposed to isolate Jabhat Fatah al Sham, a powerful Sunni jihadist group, from the rest of the rebels.
As much as (even more than) support for Assad, Iran's intervention in Syria is about a much bigger struggle against Sunni militancy -- in defence of the Shia community. So Iranian volunteers who go to fight in Syria (and there have been many thousands) are depicted as "Defenders of the Shrine" -- the Sayeda Zeinab mosque near Damascus where a granddaughter of the Prophet is said to be buried.
Turkey and Iran -- New beginning?
Amid the many shifting relationships, the Turkey-Iran one is perhaps the most important for influencing Syria's future. They've been on opposite sides of the war but while the Russians and Americans traded barbs at the UN this week, Iranian and Turkish leaders met a few rooms away.
The mood seemed cordial -- not least perhaps because Iran was among the first countries to condemn the recent coup attempt in Turkey, even as it unfolded. It also helped that Erdogan had patched up relations with Russia
, which had taken a dive after Turkey shot down a Russian fighter last year.
Erdogan described Iran and Turkey as two great Islamic countries that could work together to create stability in the region. President Hassan Rouhani agreed that there was no military solution in Syria.
Contact between Iran and Turkey has intensified dramatically in recent months -- but it's difficult to know the limits of their common ground. Both are wary of their Kurdish minorities (Iran was notably silent when Turkey intervened in northern Syria this month.) Neither likes the growing influence of Jabhat Fatah al-Sham, which is only fueled by the endless fighting; both want to see ISIS eliminated.
Both countries are devoting substantial resources -- men and money -- to the Syrian conflict. Both agree there can be no military victory, for anyone. And the Iranians will pursue any alliance that weakens Saudi Arabia, their regional nemesis across the Gulf. If that means working with Turkey and Russia, no problem.
"For Tehran, the battle over Syria is also a central part of its regional rivalry with Saudi Arabia," writes Mohsen Milani in Foreign Affairs
. "Iraq, Lebanon, Syria, and, to a much lesser extent, Yemen are the battlegrounds in this rivalry."
That's not to suggest there's trust and respect between Tehran and Moscow; there isn't. But for now their interests coincide, in building a counter-balance against the alliance of the US and the conservative Gulf monarchies.
All about Assad
Ultimately, however, there's the "Assad question." Erdogan wants Assad out. Iran has been literally fighting to keep him in place. So has Russia. But the Turkish Prime Minister, Binali Yildirim, recently suggested Assad could remain through a transition period.
"He's one of the actors today no matter whether we like it or not," Yildirim said last month. For his part, Rouhani stopped short of offering Assad unconditional backing during interviews in New York this week.
Can a different formula emerge for a political solution: one that maintains the Syrian state minus Assad, that keeps the country's external borders intact but provides space and autonomy for Shia and Sunni? How would the Kurds -- who have already created their own autonomous region -- be treated?
Such a path doesn't look plausible at the moment, especially given that the Sunni identity in Syria is increasingly bound up with militant groups such as Jabhat Fatah and Ahrar al Sham. And the Russians are not convinced the Syrian state could even survive without Assad. But there are no other solutions on offer -- as officials in the Obama Administration frequently point out.
Ultimately there has to be some convergence between not only the US and Russia, without whom no deal can be reached -- but also among regional powers, without whom no deal can be sustained.