I think we need to re-read this book and pay attention to the culture he created.
The world Heinlein creates here is the real goal of all progressive/liberals. A sustainable culture where only really important people can have an "Authorized Power Vehicle" and all us peasants are getting around by horse, public transportation, or on foot. No, there is no oppressive big brother or dictator to fear, just a system that can not be changed. Ever.
Be reasonable, you can't expect freedom or a "bill of rights' to work when the population of North America is the same as India!
Malthus is not just taught in the schools of the rich, it's ingrained as a belief. A religious dogma. In the future, limited resources will only allow a late 20th century standard of living to a limited number of people; the ruling elite.
Remember the flap about John Kerry's yacht? Well, the Liberal Goal is for that yacht to be invisible.... to you.
This is the future world that Liberals are working toward.
Gun Confiscation is the First Objective so Universal Registration is the first step.
Then comes confiscation; civilians first, then the Police, then the Military.
Use each step by step to get to the next phase.
In the end, we will all be as happy in our assigned places as the peasants were in the middle ages.
God Bless Us All, and Keep Us In Our Proper Stations.
Its a great cautionary tale.