Putin had hopes that 2026 would be the year Russian forces seized contested lands in eastern Ukraine.
Ukraine has gained territory this year while inflicting massive Russian casualties through innovative drone warfare.
The shifting battlefield dynamics offer Trump potential new leverage to negotiate an end to the war.
AI-generated summary was reviewed by a CNN editor.
Brett McGurk is a CNN global affairs analyst who served in senior national security positions under Presidents George W. Bush, Barack Obama, Donald Trump and Joe Biden.
