We need a hierarchical addressing architecture, so when you (in the USA) want to talk to Amazon you say "talk to Amazon" but when I (in an oppressive regime) want to talk to Amazon I say "talk to Tor gateway, tell him to talk to Timbuktu exit node, tell him to talk to America, tell him to talk to Amazon"

We have something like this with phone numbers (dial 9 for outside line) and domains but not with IP addresses. The "internet" used to have it with bang paths.

Flat addressing is very good and convenient, but political turmoil easily destroys it, as Russia has already seen and the US is about to see.

(Cryptographic flat addresses don't suffer political problems but have different problems with scalability)

It would solve NAT, too.