T HE TIMING could not have been worse. Days before a crucial summit in Alaska between Donald Trump and Vladimir Putin, scheduled for Friday, Russian forces broke through Ukraine’s defensive line. Near the breakout area at Dobropillia, just north of the Ukrainian stronghold of Pokrovsk in the Donetsk region, soldiers report panic and confusion.

"We talked about a ceasefire today. President Trump said this is one of his priorities in conversation with President Putin," President Volodymyr Zelensky said.

President Trump has largely held back from harsh criticism of Vladimir V. Putin personally, despite recent complaints about Russian intransigence in ending the war in Ukraine.