When we look at modern society today, there is practically no city that is self-sufficient. Metals are produced in one part of the world, paper somewhere else, cell phones yet somewhere else.  The list could go on.

But this situation exists because no city truly needs to be self-sufficient. People can purchase goods from wherever they can be produced at the best price and quality.

So, are there no places on Earth that are self-sufficient?  Actually, there are.

Self-sufficient places tend to be rural and poor.  For example, islanders have survived for many centuries hunting fish and gathering or growing basic food stuff.   

But neither the examples of urban or rural settings are altogether helpful in determining what it would take to go from a manned lunar landing to the first self-sufficient colony.  The reason is that the simple rural environment provides ready resources which are not available on the Moon.  These six fundamental things are: air, water, food, protection from cosmic radiation, temperature control, and sufficient gravity.

So, what would it take to secure these on a self-sustaining basis?  Would one need much of the technologies which modern civilization offers or could there be a small set of technologies which are sufficient and themselves could be replaced indefinitely?

The six fundamental things not easily available on the Moon can none-the-less be developed.  For example, plants require carbon and nitrogen (among other things).  Carbon and nitrogen is present in adequate amounts in the icy regolith of the lunar poles.  But what would it take to get that?  One cannot send a colonist out with a shovel because, in time, they would be exposed to too much radiation.  So telerobotic mining equipment may be necessary.  But then how could the various parts of a pretty sophisticated piece of equipment be produced in a self-sustaining way?  Does one need a full civilization of tens of thousands of people in an integrated economy?  Or, could creativity be used to create a telerobot that works adequately but which may be wire controlled.  Before the advent of integrated circuits, engineers had to use their creativity to solve problems like these.

So, my appeal is that those with the technical know how need to figure out just what exactly is the lowest technologic way to achieve a self-sustaining off-Earth colony.  If it can be figured out how to achieve these things with a relatively small colony, then we may be able to achieve he first self-sustaining colony within a relatively short while after humans return to the Moon.