Lately, everyone has been talking about IBC, message passing, various bridges, and the more I look, the more I want to draw a "trust chain" as a symmetrical diagram... But as I started drawing, I found it both funny and frustrating: a cross-chain transaction is essentially breaking down "who I trust" into several parts. The set of light clients at least has a logical closed loop: I trust the consensus and validation rules of this chain, and I can verify it step by step along the validation headers; but many bridges are actually "I trust a group of people / a multi-signature set / a relay service not to act maliciously," plus "don't write malicious contracts, don't let oracles go biased." Modularization and the DA layer have recently excited developers immensely, but users are often confused, which I can understand... The more components there are, the more responsibilities are dispersed, and when something goes wrong, it’s harder to pinpoint blame. Anyway, when I look at cross-chain now, I first ask: who’s ultimately responsible for the security of this message? Asking this question makes me feel half at ease.