I don't know how I feel about this. IPv6 is the obvious answer, but maybe some kind of NAT is warranted for devices that tend not to have firewalls?

If each LTE terminal has a publicly routable IP, unless it's statefully firewalled, any random Internet user who can figure out my IP can run up my data bill, or packet me and inflict a Denial of Service. I remember long ago, some mobile operators in the U.S. were assigning public (non-firewalled) public IPv4 IPs to mobile devices... Attackers were literally scanning Sprint's mobile IP ranges for open port 22 and logging in over SSH as root/aspen to hack jailbroken iPhones!