While Marx and Engels wrote detailed critiques of capitalism, they could only suggest the bare outlines of what socialism as the order of society supplanting capitalism could be like. Lenin built on these ideas and the experience of the working-class movement to develop notios of the ways in which a transitional regime based on the worker-peasant alliance could open the path to socialism. Stalin guided the construction of socialism in 'one country' (Russia), and analysed the problems faced by socialism once extablished. Mao Zedong critically reviewed the experiences of the Soviet Union in socialist construction, and insisted that one must grapple with and resolve various contracdictions within socialist society that he went on to define.