Blinken, in New Delhi for talks with Indian leaders, said the only path to peace in Afghanistan was through negotiations, which all parties must take seriously.
Taliban insurgents have swept through districts across Afghanistan and seized vital border control points in recent weeks as Washington has withdrawn its last troops after 20 years. The Pentagon now estimate that the Taliban controls more than half of Afghanistan's district centres.
The Taliban banned women from education and work and carried out public executions of their enemies when they last held power from 1996-2001, and millions of people fled their rule.
They say they will treat civilians well if they return. Peace talks in Qatar have largely stalled.
Describing reports of attacks on civilians as "deeply, deeply troubling", Blinken said: "An Afghanistan that commits atrocities against its own people would become a pariah state.
"There's only one path, and that's at the negotiating table, to resolve the conflict peacefully."