Early on Sunday morning, Colonel Sergei Storozhenko, the commander of Ukraine’s 36th Coastal Defense Division, looked through the gates of his base in the center of Crimea, in southern Ukraine, to see a column of Russian troops approaching. He estimated there were roughly 800 of them, a full battalion, which would outnumber, if not outgun, his Ukrainian force of several hundred men. Without identifying themselves, the Russian troops took up positions within easy range of the main gate and ordered the Ukrainians to lay down their arms and surrender the base. Storozhenko and his fellow officers refused, deciding that they would, if necessary, stand and fight.