Explain SMBC — the wiki for Saturday Morning Breakfast Cereal

The Joke

An alien visits Earth and explains that "conservation of energy is a political law, not a physical one." The alien reveals that if too much extra energy is created, the universe could collapse, so the mechanism for creating energy is kept very complicated and rare in nature. However, the one remaining risk is that an intelligent species could discover the mechanism and use it for their own benefit.

The twist comes when it is revealed the aliens aren't here to stop humans -- they're actually tourists. They've come to see "the only species that has figured out sex robots prior to figuring out free energy." The alien then asks for a photo with a human, treating humanity as a novelty attraction.

The Humor

The comic subverts the typical "aliens come to warn/stop humanity" trope. The setup builds tension suggesting the aliens are concerned about humans discovering unlimited energy, but the punchline reveals that humanity's priorities are hilariously misaligned -- we developed sex robots before solving the energy crisis. The aliens find this so remarkable (and presumably unique in the universe) that they've come as tourists to gawk at us. The humor also plays on the real-world observation that technological development is often driven by prurient interests rather than noble goals (a common joke about the internet being driven by pornography).

References

• Conservation of Energy: A fundamental principle of physics stating that energy cannot be created or destroyed, only transformed. The comic reimagines this as an artificial constraint rather than a natural law.
• The "sex robot before free energy" joke echoes the common observation that the internet's development was substantially driven by the adult entertainment industry.