Feeding the new push for diplomacy has been the growing recognition that the Russian invasion has badly stalled, with Moscow taking huge manpower and equipment losses. Biden aides, buoyed by Ukraine’s military campaign to date, nevertheless scoffed at the suggestion that Putin was ending the war, instead believing he likely was temporarily focusing on a more winnable region, the officials said. The Donbas region — parts of which have been held by Kremlin-backed separatist forces since 2014 — appeared to be a particular target.

Putin’s campaign has gone so unexpectedly poorly that U.S. officials have begun reviewing their own intelligence assessments to determine how they could have so badly misjudged the strength of the Russian military. Despite pouring billions of dollars into modernizing Russia’s military, Putin’s forces have been saddled with poor equipment, communications and morale — all leading to, so far, a stalemate against a much smaller and overmatched foe.

To that point, one U.S. official bluntly said: “The Russians really fucked this up.”