World Peace

To me it is incomphrensible that we, as humanity, have not figured out a way to stop killing eachother.

Is world peace desirable?
How would you go about attempting to acheive it?
What problems would your system create?


I'll go first.

Yes, world peace is desirable. My system would be as such :

The creation of a group of nations (called the U.N. here) which has two policies. You must be a democracy with a bill of rights to join and any member state has the freedom to be safe from any hostility.

The bill of rights would include :
Universal suffrage
Fair trials
Freedom of speech
etc.

On application to join the U.N. will enter the country militarily and hold a referendum on whether the country wishes to join. If it does, the U.N. will then hold internal elections and add the nation to it's military alliance.

All armies from these nations will not be seconded but rather firsted to the U.N.

Of course this is just a rough frame work, but that is how I would do it.

How would you?