According to geopolitics, maritime nations tend to be easy to develop commerce and have the decentralization of power, as a result, the people of maritime nations tend to have strong individualism, making it easier for democracies to take root. To be honest, I don't really get it (because I don't think Japan is particularly strong in individualism), but I think it does make a certain amount of sense as it explains the differences between Japan and China.

There are techniques to encrypt a secret key with a password as a salt. For example, the master password of a password manager, proton mail cloud syncing, or NIP49 used in the Nostr client. If this password is not filled with the auto complete of the password manager or OS/browser, it is likely to be simple and easy for the user to remember, so it is likely to be a placebo that can be cracked by brute force attacks. We learned this from the LastPass leak incident and are now staring coinos.

DIDの鍵ローテーションの基本設計は鍵の切り替えが起きる前の過去の署名は有効に扱い続けますね。署名そのものは改ざん不可能なので、どの時点から攻撃者が作成したかのタイムラインが肝要になります。このタイムスタンプの信用を確保するために鍵のライフサイクルイベントの保存にブロックチェーンが使われがち。