New World Order

Abstergo Industries' final goal seems to be to create a New World Order. They plan to do this using the power of the Pieces of Eden, thus the reason they kidnapped Subjects 16 and 17 (and presumably the ones before them) to find these relics. In Assassin's Creed, Warren Vidic mentions how human society has been barbaric since its earliest days and is in a great need of order, discipline, and control.

The Pieces of Eden themselves are integral to the plans of the Templars; their abilities to influence the minds of people near the operator have been prized since the time of the pre-Sumerians at the latest, judging from their ubiquity in art and warfare of the time. The Templars' order would be one of so-called "benign tyranny", as although the Templars would eliminate racism and the petty machinations of the warlords and princes of their time, they would simply replace that disordered chaos with their own arbitrary Order. This plan seems to have been in existence since the Second Crusade at the latest, as even the first waves of Templars in the siege of Acre in the Third Crusade were already fully aware of the plan. Moreover, the means by which the Templars mean to establish this Order seem to be unchanging: collect as many Pieces of Eden and other relics of 'Those Who Came Before' as possible, and use them to brainwash the peasantry of the world.

As their very cause is to collect the fantastic sources of knowledge locked in the Pieces of Eden, the Templars' Order is equipped with some of the most advanced technology of the periods in which it was active; the machinations of Robert de Sable and Garnier de Naplouse during the Third Crusade include the making of drugs and medicines which the world had never before witnessed.

The proclaimed New World of the Templars seems to based on the 'utopia' ideal, a world completely free of bigotry, but the Templar ideal seems to differ in the establishment of a small ruling elite controlling all education, military force, and food distribution.

The Templars' plan for a New World Order is to use the Pieces of Eden to control every human being on the planet. They plan to launch a Piece of Eden into space, in connection to one of their satellites. Through the combined power, the Templars can activate it to control the minds of every human being on the planet. The Templars believe that by completely controlling others, they will bring peace to the Earth.

The Templars plan to launch their Piece of Eden on December 21, 2012.

Trivia

 * December 21, 2012 is the date the Mayan calendar ends, corresponding with what the Mayans believed would be the day the world ends.
 * Near the end of Assassin's Creed: Brotherhood, continual references are made to the number 72 - including the fact that there were 72 days left before the Abstergo satellite launch. Other references included Exodus 14:19-21 (the 72 names of God) and the number 72 being the password to enter the Colosseum Vault.