You can absolutely replace SMTP but whatever you replace it with needs to be at least compatible with it. Lots of warnings, Insecure Email Ahead, but it needs t

You can absolutely replace SMTP but whatever you replace it with needs to be at least compatible with it. Lots of warnings, Insecure Email Ahead, but it needs to be compatible. I also don’t think email should be e2e by default. Next gen email will never get adopted if Gmail can’t index it. What you want is to give them the option of selling “Secure Cloud Email Vault.” Something that’s encrypted or partially encrypted (just body) on their servers, like Amazon is selling encryption for S3. But the protocol can also support fully local encrypted email (as detailed in my previous) for those that want that. Edit: Oh also for the actual cryptography there needs to be a way to give someone (like Court Order) decryption key to a single message. This avoids a lot of issues. Governments are not just going to let you deploy fully encrypted email by default.