This week’s chemical attack on civilians has changed President Trump’s attitude toward the intractable civil war in Syria. At a Rose Garden press conference with King Abdullah of Jordan, Trump condemned the attack and the brutality of Bashar al-Assad’s regime.

“It’s very, very possible, and I will tell you it has already happened, that my attitude toward Syria and Assad, has changed very much,” Mr. Trump said. “I think the Obama administration had a great opportunity to solve this crisis. When he didn’t cross that line, after making the threat, I think that set us back a long ways. It was a blank threat.”

When a reporter asked if Assad’s apparent use of WMDs crossed a “red line,” Trump said it did. “When you kill innocent children, innocent babies, little babies, with a chemical gas that is so lethal — people were shocked to hear what gas it was — that crosses many, many lines, beyond a red line, many, many lines,” he said.