And yet there has been little public outcry in the United States over the military offensive and only belated and half-hearted efforts by world powers to stop it. News of the slaughter in Ghouta seems to be all around us, even as news of serious efforts to end it is nowhere to be found.

The United Nations expert Richard Gowan recently suggested one cause of death for the CNN effect in Syria. Today—with the effect of unverified social-media posts and slick state propaganda on a civil war wrapped in a proxy war inside a great-power war—“we have a fragmented media landscape: different images, different narratives, no facts beyond doubt,” he wrote on Twitter. He pointed to how the UN envoy from Russia, which is allied with Syrian President Bashar al-Assad, had opposed a recent ceasefire proposal in the Security Council. The Russian diplomat had argued that press accounts of mass murder in Ghouta amounted to “mass psychosis” that overlooked an “inconvenient truth:” Extremist militants were attacking Damascus from bases inside hospitals and schools. “When there is no common agreement on what is true, you can’t speak truth to power,” Gowan noted.

“What we’ve been seeing over Ghouta is something that we’ve seen increasingly frequently in UN debates over Syria, which is [U.S. ambassador to the United Nations] Nikki Haley, the Brits, the French coming to the [UN Security] Council trying to shame the Russians, using the fact that we have so much horrific evidence of what’s going on on the ground … and the Russians not merely ignoring that but effectively questioning whether [it’s] fake news—implying that everything is propaganda being produced by the rebels,” Gowan told me.

Gowan recalled how NGOs and Hollywood activists had marshaled evidence of genocide in the Sudanese region of Darfur to pressure China into supporting a UN peacekeeping force in Sudan in the run-up to the 2008 Beijing Olympics. “That sort of extended media-driven shaming process would just fall apart in the current environment,” he said. “Now it would be so easy for trolls and spoilers to undercut that campaign.”

Visuals of human misery in Syria have occasionally cut through the noise. In 2015, several countries staked out more welcoming positions on Syrian refugees partially in response to a viral photo of a dead Syrian boy washed up on a beach. Two years later, U.S. President Donald Trump cited pictures of stricken children as one of the reasons he decided to strike the Syrian military for using chemical weapons against civilians. Trump’s reaction was “a reminder of how the CNN effect was meant to work,” which was fitting for “a cable-news junkie,” Gowan said. But these humanitarian interventions have been ephemeral (sympathy for refugees quickly faded, Trump’s strikes were a one-off) and arbitrary (many hundreds of boys and girls have died since the boy on the beach, the Trump administration has held its fire as Assad has unleashed barrel bombs and chlorine gas on his people).