Praetorians represent the pinnacle of military training, infantry scaled armor, and cybernetic augmentation and integration for the Terran Sovereignty. The end result of these efforts is the most capable and dangerous Terran soldier in history, one which the Sovereignty is increasingly confident will turn the battlefields of the near future to their favor against alien combatants such as the Ukaros.
Virtually every army in history has deployed specialized troops who are better armed and better trained than the so-called "rank and file" soldiers. Such special forces have then been used to achieve the most difficult battlefield objectives, and have often been involved with the internal politics of their governments... sometimes as a force for stability and sometimes the opposite. Understanding the unique role such forces played throughout Terran history is important to understanding the role of the Terran's most advanced special forces units known as "Praetorians" serve within the Terran Sovereignty today, as is the history of the most recent large-scale conflict involving Terrans prior to the Sovereignty's founding... the Monroe Wars.
It is no secret that the Terran Republic found itself deeply unprepared for the Monroe Wars... Terrans exodus to the stars and colonization of other planets was haphazard, uncoordinated, and ultimately brash. The Terran Republic found itself nominally responsible for defending colonies it wasn't even aware it had founded, and they had nowhere near the navy required to do so. As a result, the Terrans drafted commercial vessels and their crews into their military navy. Those crews often included mercenary forces that were then deployed in ground combats.
On the ground, Terrans were arguably much better prepared... unlike some races, the Terrans had experienced near un-ending periods of conflict and war on their homeworld and they were no strangers to training disciplined and professional soldiers. Thusly, one might have expected Terran ground forces to perform well during the conflict... they did not however. There is little academic debate over why Terran soldiers fared poorly during the Monroe Wars... they were simply outclassed by their opponents... the Ukaros. The Ukaros are stronger, faster, have greater reflexes, and endurance than any Terran by a wide margin... on the ground the Ukaros deployed few soldiers, but each was clad in powerful mechanical suits of armature and armor that allowed them to wield not just heavier weapons, but numerous weapons, all synchronized to the Ukaros Warrior's brain. Aside from this, Ukaros Warriors can live for many centuries and their culture is dedicated to maintaining a large caste of individuals dedicated to the practice of war and war alone.
The Monroe Wars ground combats read as a litany of terrifying and brutal engagements where Terran forces outnumber the Ukaros by dozens or even hundreds, and are simply slaughtered by a technologically and biologically superior enemy. Further compounding the issues, was that the nature of the Terran navy (being ad-hoc and non-standardized) often limited the amount of heavier armored units that could be deployed to a battleground. The Terrans were forced to rely on infantry and that infantry was simply not up to the job.
Almost immediately after the founding of the Terran Sovereignty following the defeat of the Terran Republic in the Monroe Wars, the Sovereignty initiated the Praetorian initiative. The best surviving units of soldiers from the wars were recruited (some would say drafted) and their experiences analyzed and recorded. This data was then used to create an AI algorithm designed to identify those in the population who had the correct psychological profile to make similarly qualified soldiers. Aggressive recruitment measures are now used in conjunction with this algorithm to recruit for the Praetorians... it should be noted that a relatively high number of incarcerated individuals meet the profile's requirements and are forcibly drafted (if chosen under these circumstances the assignment is for life regardless of one's actual crime or sentence).
Once selected, the Praetorians undergo significant cybernetic augmentation. Cybernetic implants are used to increase the reflexes and integration between the recruit and the armor and weapon systems they are trained for. While having cybernetics to help one connect to one's smart-rifle or survival suit isn't unusual... the extent to which this is done for Praetorians is extreme. Praetorians do not consciously monitor their suit vitals or weapon ammunition the way normal augmented humans might... by seeing a HUD in their eyes/brain that they then read/interpret... instead a Praetorian simply feels these things... he know he has 71 rounds in his weapon as readily as anyone knows that they have 10 fingers or 10 toes.
Selected and physically modified, Praetorians are then armed with the latest and best weapons and armor the Sovereignty can provide. This, combined with a professional navy and improved armored support for any combat operation, goes a long way towards evening the gap between Terran and Ukaros forces, enough-so that even the Ukaros do not believe Terrans will be "easy fights" on the ground. However, improved logistics, gear, and strength still does not make a Terran soldier equal to an Ukaros who has trained for centuries and is still stronger and faster (though not necessarily faster reacting anymore). Thusly the final "adjustment" made to Praetorians, and what makes them unique within the Terran military is the use of psycho-therapy and cybernetics to implant an artificial sub-personality matrix within the soldier.
This sub-personality isn't a true "person" or such, but instead a carefully crafted series of behaviors laid underneath the existing personality... behaviors that the soldier cannot actually control or deny. This "special training" has resulted in Praetorians exhibiting a variety of traits such as:
When significantly injured Praetorians stop feeling pain, they can endure loss of limb and while they might be personally horrified, this will not impact their tactical thinking.
Praetorians cannot surrender, if captured, they cannot help but refuse food and water until death or escape.
Praetorians will follow orders like any soldier, but if given certain security codes in relation to a particular order, they are physically incapable of disobeying or ignoring it. Such codes are commonly known as "Black-Doors".
Any form of phobia will not impact the performance of a task or mission... long term stress as a result is not considered an issue.
Praetorians can control their heartrate and breathing perfectly, even to the point of killing themselves if given a Black-Door order.
Aside from these "inhuman" traits, the Praetorians are subjected to a number of more subjective psychological manipulation to indoctrinate them into being completely loyal to the Terran Sovereignty. Finally... and most secretly, Praetorian soldiers implants have a direct connection to the same AI network used by the Sovereign himself... which means that so long as a network connection is available the Sovereign can issue any order to any Praetorian (subject to any communication time-delay that may exist within the network).
While it is unknown exactly how many Praetorians exist within the Sovereignty... the nature of most ground conflicts in modern interstellar warfare means that one usually only needs a few hundred or thousand soldiers for a given battle. Thusly, there isn't a precise need for large numbers of Praetorians. Regardless, today the Praetorians represent the greatest soldiers the human race has ever produced, largely in-spite of their humanity than because of it... and while anyone who has met a Praetorian can sense their dangerousness... the government has gone to great lengths to ensure that they are "controlled" in every way possible and only unleashed when their superiors (or the AI-assisted Sovereign) decides to.
Current military simulations suggest that where before a minimum of fifty Terran soldiers needed to be deployed to cause a single Ukaros casualty, it is believed that seven Praetorians are capable of the same feat, though the Sovereignty is eager to collect real-life data against the alien Ukaros at the earliest opportunity.