The question is subtly Malthusian in nature: how to deal with the world's teeming billions in one fell swoop while maintaining the existing social and political orders in all of the countries?  That order needs only to have one facade now: as Draconian an order that can be accomplished without throwing the world into a revolution against every government in existence.  The Draconian nature is as follows: CCTV cameras monitoring and cross-referencing every purchase, every bank withdrawal or deposit, every movement, and every social engagement.  The Draconian nature is one of continuous monitoring, with a rise in prices and a steadily-declining world economy, as natural resources are quietly siphoned off by the politicos and the oligarchs to stockpile for their use when the plug is pulled.

As much Draconian repression and control under a "soft" police state with continuous monitoring…while those in power lay the groundwork to collapse the system and kill off most of the world's population…while they remain safe, and in power.