I think Deng was a pragmatic figure , he understood the theory of socialism more than Mao and its leadership in later years. Mao had a hard time relating to the rapid changes in the world. Deng opened up the economy and modernized China in thought and spirit. Although China had a revolution in 1949 but it had a huge gap in technological progress and technically skilled people w.r.t west. China did the right thing and by self correcting the course and again reorienting its policy towards anti west , it brought US to its knees . Marxism is about people's development not just in paper but in real time world,