Headscratchers / 3 Body Problem

• "We're going to kill you as bugs because you are liars" simply due to learning fairy tales are untrue seems really questionable coming from the society that seems to understand creating falsehoods already:
  • Scrubbing security camera footage.
  • Creating a video game story that by their own admission includes Artistic License.
    • They understand altering of data, but not conveying misinformation through direct communication. To them, the closest analogue to verbal speech is something akin to telepathy. But in any case, the San-Ti were extremely wary about humans from the start, the only reason they didn't seek our extermination from the start was that the first attempt at communication from humans was a plea to surrender and submit to their rule.
    • Adding to the above: deception does exist within their culture, but it's very indirect since the aforementioned "telepathy" makes outright lying futile and thus they have very little experience with detecting the latter. For them, deception mainly consists of withholding data, erasing evidence, and avoiding detection, which does match up with their behavior regarding Earth. And metaphors and Artistic License are not inherently deceptive; "you are bugs" was a taunt, and their human alien appearance in the VR game was explicitly A Form You Are Comfortable With.
    • The problem occurs because of exactly what the "Lord" considers lying. They are confounded by Mike Evans metaphorically comparing their enemies to a plague, which is a direct parallel to them calling humanity bugs later. And the concept of fiction, as in a fairy tale not being true, also seems beyond their initial comprehension, which should make the fictional elements of the video game likewise alien to them.
• If the aliens are so advanced that they've got intergalactic travel, quantum computers the size of a photon, and cam observe a planet over 3 light years away, why do they need Earth? Presumably they've also been observing other planets that they could look to colonize or terraform (assuming they've got the technology to do so).
  • They don't have anything resembling intergalactic travel. Just the cosmically short distance of four lightyears takes them all their resources and four centuries to accomplish. There are no habitable planets closer than Earth to them. And if they didn't have a need for Earth, they would just have sterilized the planet without saying a word to us. They don't want to destroy humanity because they want our world, they want to destroy us because we are a potential threat no matter what. Wanting Earth is the only reason why they entertained coexistence even for a moment.
    • The aliens have evolved to survive far harsher conditions than anything we would consider "habitable". They're only leaving their planet because of its unpredictable orbit, which causes Chaotic Eras and will eventually destroy their world. There's not much of a reason they can't just park their fleet in our solar system and keep most of their people dehydrated while they mine asteroids for resources and "terraform" Mars or some other non-Earth planet — except for their distrust of humanity and the needs of the plot.
    • You're correct that the San-Ti don't need Earth specifically; any stable world in the Solar system would do. But Earth is treated with near-reverence in their society because it's a stable world that also happens to be habitable to their kind, and it's just four light-years away — practically on their doorstep. Culturally, it would be unthinkable not to conquer Earth. On top of this, they resent humanity for having had the freedom to develop without becoming ruthless social darwinists, and feel entitled to our planet as a reward for having suffered through so much in their long history.
• Is it explained how a row of 300 nuclear devices was positioned along an impossibly long course through space for Project Staircase? How did the bombs get there, and wouldn't it take a huge amount of time for bomb 300 to reach its outer position in the chain?
  • According to the books, launching the nukes into orbit began very early in the project, before most of the technical details had actually been finalized, and these launches continued all the way through development. Presumably some of the earliest launches were aimed at the most distant orbits at the end of the chain, so all the bombs would be roughly in position by the time Will's rocket lifted off. It's also implied that, unlike in the books, all the bombs were placed in or near Earth orbit, so reaching them would only take a few days or weeks under normal interplanetary speeds.
• If the Sophons can cause every digital screen on Earth (including ones unconnected to the internet like the recorder given to Ye Wenjie) to show the same thing at the same time, why do they only use this for intimidation? The havoc caused by all computers, televisions, cell phones, and so on suddenly becoming inoperable would at the very least significantly hamper humanity's scientific development in the short term and possibly even knock us permanently back to a pre-digital age, and since the aliens have already stopped hiding themselves, there's not really much of a downside for them to use such a tactic.