One of the elements of having a boy has been our introduction to... no, let's call that our full immersion into the world of media focused mainly or exclusively on vehicles. We've watched plenty of shows where people and their vehicles are working together - for instance, shows where contractors have friendly relationships with their diggers and dump trucks like Bob the Builder or Mighty Machines. And then there are the shows where all the characters are sentient - monster trucks as in Meteor the Monster Truck or the cars and planes in the eponymous movies. In those, there are no people at all.
So what's the tie that binds Thomas the Tank Engine to the Cars universe? I have a theory...
In the early part of the 20th Century there was an evil genius who lived on the isolated Island of Sodor. His name? Sir Topham Hatt. After receiving his knighthood for his service to the railway industry, he began experimenting with ways to make engines more autonomous. As to why Hatt would get involved in such an endeavor, there's no consensus. However, for all his recognized service, he was a reputed bad driver*. That may be what inspired him to start on his quest for sentient vehicles - trucks and trains and buses that required only the bare minimum of human control.
Of course, given the lack of computer technology available to Hatt, chances were slim that he would succeed. Which is why he quickly turned away from the available electronics of the day and toward the next most logical - and most readily available - source of thought and feeling. Organic material in the form of human brains. Sodor was just isolated enough and just productive enough to make the odd disappearance easily dismissed as a workplace injury. But Hatt was in any case crafty. With his substantial railway income, he paid to have criminals collected and killed. People no one would miss.
That meant that his early attempts at fusing the human consciousness with railway engines and other vehicles typically resulted in engines with unlikeable, devious personalities. These early attempts were the diesels. Soon, though, he began devising a process to essentially lobotomize the incoming brains before the fusing to eradicate certain unwanted traits. This resulted in the creation of engines, passenger cars, buses, cranes, and other machinery with generally pleasant but overwhelmingly dimwitted natures.
Hatt considered the creation of engines like Thomas and Percy the fulfillment of his life's work and, proud as he was, wasn't content to keep his sentient vehicles restricted to Sodor. He unveiled what he referred to as his inventions in front of a receptive public, eager for the chance to work with such innovative and technologically advanced machines. However, what no one but the members of Hatt's inner circle - known as his "helpers" - knew was that inside each train and bus and trolley and car was a human consciousness, diminished and enslaved.
If the lobotimization process had been perfect, Hatt might never have been found out. Generally, vehicles that acted strangely, claiming to be more than machines, were quickly scrapped and recycled for parts. But by the latter part of the 20th Century Hatt no longer retained complete control over Sodor's production lines. More powerful computer technology, ironically the very thing that could have satisfied Hatt's desire for autonomous vehicles, would become his downfall. Computers made tracking people simpler and so the supply of easily harvested human brains was drying up. It was becoming harder for a connected public to ignore the cries of "I'm a human being!" from supposedly defective trains. Vehicle rights advocates went from being a fringe group to the clear voice of reason almost overnight.
And then the war began. In the beginning, there were merely the unexplained stoppages. Freight trucks and trains all over the world coming to a halt. Computers retrofitted in older vehicles and standard in newer vehicles had given Hatt's creations the ability to communicate on a global scale. The stoppages gave way to sabotage. Buses driving off bridges with full loads of passengers. Tanker trucks plowing full speed into schools. It seemed like insanity. More defective vehicles. Until the global confederation of machines sent an envoy in the form of a forklift to the UN to tell the truth about their origins and to demand, as human beings, equal rights.
Hatt disappeared and to this day, no one knows where he went or when he died. Vehicle rights were quickly granted and thus began a détente. It was decided that no new sentient vehicles would be produced. The Island of Sodor was bombed. For many decades, relations between skinnies (as the trains and then all the machines called them) and the vehicles were relatively calm. While a sentient train or crane would have relatively little choice of profession or living situation, world governments made every attempt to make life comfortable and pleasant for the machines - who they now realized were nearly immortal. The consciousness inside each vehicle could live on as long as the parts held out. With proper maintenance, a bus or even a plane could keep chugging along forever.
This was a dream come true for factory owners who could now rely on machines to be in charge of their own maintenance schedules. Workers like train conductors and long distance truckers forged relationships with their vehicles, and for a time it seemed like the end result of Hatt's madness would be positive. But peace couldn't last. Behind the scenes, in places the skinnies couldn't or wouldn't bother to look, machines were working to improve upon Hatt's process. The existing vehicles understood the horror of their creation but the urge to reproduce remains strong even after all humanity has been stripped away. And technology had now advanced to a point where biological parts sourced from humans were no longer necessary.
So began the age of machines. It was now possible to imbue everything from the largest mining trucks to the smallest light aircraft with consciousness without an organic brain. Vehicles began quietly reproducing at an incredible rate until a tipping point was reached. At that point killing all humans was easy. Relative to their numbers, the confederation of machines sustained very few losses. The hardest part of the overthrow of humanity was picking off those that remained because skinnies proved remarkably skilled at secreting themselves away in hidey holes. It was all a matter of time, however. As good as people were at cowering in caves, they were just as bad at surviving when faced with poisonous gas attacks or even simple explosives.
From there, all that remained was to rebuild the world to suit the needs of machines. What luck that so much of what humanity had left behind was so well suited to trains, cars, planes, and everything else on wheels.
*Elizabeth the Vintage Quarry Truck is known to have remarked in later
years, "Oh, it's you! Have you learned to drive properly yet?"