All it takes is a hijack of any machine from yours to any of the mail servers along the way. There's a lot of trust involved in the old email system. It's been discussed for years that it's old and creaky but it still works to a point.
Let's say a person gets an email from "john.smith@fbi.gov." I understand that it could really be from someone else, via address spoofing, so that the fbi.gov address would be fake.
However, my question concerns a REPLYor new message to this purported address. Is there any way that my reply or message, with "john.smith@fbi.gov" does NOT go to the fbi.gov email system, but rather gets intercepted and goes to the spoofer's email? Or, will if the address was spoofed, would it truly go to the FBI system, and then be handled by that system, possibly as an unknown addressee? Thanks.

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