So much for the constitution.
It's right there in black and white. Article I, Section 8, Clause 7: "To establish Post Offices and post Roads and mandate the use of high-tech tracking stamps so that no one has the ability to mail a letter, package, or cardboard tube with anonymity."
What's that, Mr. Postmaster General? You want me to use smart stamps? Well, lick this!
This country's going to he** in a hand basket and fast.