Putin for years has snuffed out dissent, muzzled independent media and bolstered a security state to prevent protests, meaning he faces far fewer domestic constraints in waging such a war than the leader of a democratic nation would. Continued revenue from foreign oil and gas sales, despite Western sanctions, also is helping him ease the blow of harsh economic sanctions at home. But Putin does face certain tactical strictures on the battlefield, as well as some geopolitical and economic constraints. They all will probably make his ability to wage a long war in Ukraine more difficult but far from impossible.

“Time is not on Putin’s side,” said Russian political analyst Tatiana Stanovaya, founder of the consultancy R. Politik. She noted that, as the war grinds on and the sanctions set in, the fallout on Russia from the war is likely to compound.