Geneva, Switzerland(CNN) Ahead of renewed peace talks between US Secretary of State John Kerry and Russian Foreign Minister Sergey Lavrov there is a sense of foreboding.
What I am learning here is just how abandoned Syria's vast population that is against Syrian President Bashar al-Assad feels and how much international pressure there is on them to sue for peace.
No matter how brightly the sun shines on the crystal-clear waters of the city's fabled lake, the chill of "realpolitik" hangs in the air and its dark labyrinthine ways shroud the looming discussions.
Opposition negotiator Bassma Kodmani tells me their pleas over recent months to the United States and United Nations for help have gone unanswered. "We ask and hear nothing," she says. "Silence."
It feels as if we are being told, she adds, "You figure out what's best, you figure out how to save your people, because we're [US and Western allies] not going to help."
Just last month, Daraya, one of the many rebel-held suburbs of Damascus, that have held out through 4½ years of siege capitulated to regime demands of surrender.
On Tuesday, Kodmani told me another suburb ,Moadameya, home to 45,000 people facing the same agonizing decision, an ultimatum from the government to turn over 6,000 military-age males and end their resistance. The alternative, they feared, was to face the full force of Assad's fighter jets and barrel bombs.
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Indeed in Geneva, realpolitik does seem to rule the day. The message the opposition perceives is the one their erstwhile Western allies want them to understand.
A Western source close to the talks tells me it's terrible these opposition suburbs have to surrender after suffering such deprivation and hardship for so long. Adding they don't do this because they want to, but because without the hope that help is on the way they just can't face holding out any longer.
What they are hearing from their allies is "you need to decide how you can end the suffering of your people" but do that in the knowledge no international force is coming in to help you out, the source said. It is a frankness I've not heard before.
In part, it seems the pressure on rebels is ratcheting up because the longer the talks go on and keep stalling as they have this year, and previous years, the more it becomes clear the United States has little leverage over Russia, and even less over Assad.
So while John Kerry will seek the best terms for a ceasefire, for humanitarian aid delivery, for release of prisoners, he himself is a prisoner to Geneva and Syria's realpolitik. His interlocutor Sergey Lavrov, or at least Lavrov's boss, President Putin, holds most of the cards.
The best it seems Kerry can offer the opposition is to get to durable peace terms quickly.
After the surrender of Daraya, Jan Egeland, the United Nations' humanitarian envoy, spoke passionately of the consequences if there isn't a truce soon.
"The [humanitarian] task force failed the people of Daraya, we all failed the people of Daraya, I failed them and it is really sad to think of what they went through over these years. There are now urgent fears of communities in Al-Waer, in Moadameya, in Madaya and in Foah and Kefraya. They all fear for their future, and we need to break the sieges."
The realpolitik of Geneva seems to indicate Russia holds the key. The question is can Kerry get them to use it and unlock the sieges, end the suffering and open the door to the possibility of realistic peace talks.
The answer so far has been no. For the Russians, realpolitik reaches beyond Syria to Ukraine, they want sanctions lifted, and on that the United States holds the key.