"While the meeting itself is historic " the most high-level engagement between U.S. and Iranian officials since 1979 " the chances for success appear low. Both sides know the risk of failure is renewed war, but have clashing visions for peace.

"We still don't agree on what we are negotiating about," another U.S. official said.
The countries have spent the lead-up to the talks accusing each other of ceasefire violations. The Iranians threatened not to show up at all, though state media later reported they'd touched down in Islamabad.

While Vance was in the air, Trump made a thinly veiled threat to kill Iran's leaders if they don't play ball."