Ukraine’s soldiers have blown up bridges to halt advancing Russian ground troops. Its pilots and air defenses have prevented Russian fighter jets from conquering the skies. And a band of savvy Ukrainian cyberwarriors are so far beating Moscow in an information war, inspiring support at home and abroad.

To the surprise of many military analysts, Ukrainian troops are mounting a stiffer-than-expected resistance to Russian forces up and down battle lines across a country the size of Texas, fighting with a resourcefulness and creativity that U.S. analysts said could trip up Russian troops for weeks or months to come.

The Ukrainians are also exploiting a bungled beginning to Russia’s all-out assault. Armed with shoulder-fired anti-tank weapons, they have attacked a mileslong Russian armored convoy bearing down on Kyiv, the capital, helping stall an advance plagued by fuel and food shortages, and stretching a march that was expected to take a handful of days into possibly weeks.