Arguing about anything that has to do with Star Wars is usually bound to produce one of two reactions, a heated debate that will hopefully come to a friendly compromise but usually comes down to someone being labeled ‘not a true fan’ or one party rolling their eyes and walking away. Okay, there are more variations than this, but those are two of the biggest. But thinking about how Anakin Skywalker managed to build his own protocol droid in his small home, the question appears to be how Anakin, who was 9 years old at the time, managed to accomplish this. It was thought that Watto would be involved in this discussion since Anakin was taking parts wherever he could find them and at times his Toydarian master wasn’t fully aware. Instead, it’s apparently being placed in canon that being good with machines is a Force power at this time. If you’re rolling your eyes then good, because the fact is that it’s kind of silly to say such a thing, but if one really wants to use that excuse, then it could be said that those that have a healthy knowledge of how machines work and which piece needs to go where it’s easy to think that their Force sensitivity allows them to have a deeper connection with what they’re building.
Think of it this way; over time, many people develop a certain sensitivity to their work, especially those that care about what they do. Whether it’s by habit or because they’ve become uniquely attuned to their work, these people can usually intuit what’s needed for a job without thinking about it, and are able to take on a task that they know a great deal about without fail. This is kind of a good explanation for how Anakin managed to build C-3PO, as he had the parts, the idea of how to put them together, what needed to go where, and so on. Despite being a child, it definitely feels that life on Tatooine would have aged Anakin just a bit beyond his years since survival has a way of doing this at times.
This could explain why he was so skilled when it came to machinery, not to mention the fact that he worked in Watto’s shop and had to prove himself useful so often. This and the Force, which wasn’t known to him at that point, would have given Anakin a distinct advantage when it came to building his own droid and podracer. So yes, his affinity with machines could be part experience and part Force power, which means that C-3PO was built with a mix of ingenuity and mystical ability that Shmi Skywalker might have guessed at but didn’t know about. But the next question that has popped up since then has been why Vader didn’t recognize the droid he created when he was on Cloud City and had captured Han, Leia, and Chewie? C-3PO was a jumble of parts at that point, and one explanation could be that a lot of protocol droids do look alike, but it also feels as though there would have been recognition, perhaps an echo in the Force, that he might have felt.
There is actually a graphic novel that features a short story detailing C-3PO’s life as he’s brought online first on Tatooine. The ending of this tale sees Lord Vader holding the droid’s head, then touching it to his own helmet before telling a trooper to take the pile to be destroyed. Obviously people should be able to see this for what it is. In the comic, Vader remembered creating the droid, he remembered how much care and time went into the making of the droid, and in a rare moment of sentiment was drawn in a way that made it appear that the dark lord of the Sith was mired deep in regret. It’s not exactly something that would have held with George Lucas’s idea of Vader obviously, so it’s not too hard to think that it wasn’t something he was willing to include. In fact, Lucas probably had no idea what Anakin was going to be like when he created the original trilogy, so it’s kind of a moot point.
But to really give an explanation why Vader didn’t react to seeing the droid, no one but a Force-sensitive could have sensed if he had or not beneath his mask, and there was no way a lord of the Sith was going to give any obvious reaction to seeing a droid that belonged to a part of his life that he’d convinced himself was dead and gone. So as to the question of how Anakin built C-3PO, it’s easy to think that his unknown access to the Force and his need to prove himself useful collided in a very fortunate way when he was younger.