[X3D-Public] authoring environments and browsers: why both?

[John Carlson]

Why are there both authoring environments and browers/players?   
Shouldn't a browser be able to support/deliver an authoring application?
I realize the same dichotomy has existed with HTML as well--but there  
are HTML browsers which support editing, right?  Is there something  
missing from VRML/X3D which only authoring environments provide?   
Would providing these within the context of VRML/X3D make a better  
standard?

I can use vim to write vim, emacs to write emacs, eclipse to write  
eclipse, netbeans to write netbeans.  Would the combination of  
netbeans, Xj3D and X3D-Edit be considered the solution of choice?    
What is the best way to author 3D authoring environments?  Is it just  
that we aren't there yet?

Relieve my ignorance, please.  I'm sure there's some history I have  
forgotten.

John