One likely target is the nation's old, behemoth state-owned enterprises, many controlled by a clique of elite families. The enterprises still hold sway in the economy, heavily subsidized and benefiting from monopolistic pricing. Also expected to come under scrutiny is an archaic residential registration system known as hukou, which prevents tens of millions of people from moving to cities with the best jobs and schools. For all the hype about the China "miracle," economists note there are other countries that achieved huge spurts of growth in the 20th century — among them Japan and Brazil — by pouring investment into...