Well since you do not want to use chemicals I suggest that you remove all the exsisting gravel and place it in a wheelbarrow. Then use a garden tiller or hard rake and shovel and remove all the weeds. Normally I would spray the area with round up or other grass and weed killer to prevent them from quickly returning.
Next place a good brand weed barrier down. You can substitute tarp, bisqueen or even trash bags if you prefer however these methods tend to hold more water then weed barrier so if you decide to use trash bags for instance I would put a few small nailpunch holes in them to help reduce water retainage. Next wash off your remaining rock and place them back in the driveway and add the newer gravel on the top.No method you use is ever weedproof so I reccomend spraying about once every 3 months with a good weed killer or hiring a landscape service that specializes in lawn chemicals , hiring the neighbors kid once a month to pull them or pull them up when you see them starting to appear but be sure to get all the roots.
Good luck with your driveway.
You could try what they do with railroads - a weed burner. Rather than dump chemicals into the enviroment get a weed burner. You hook it up to a propane tank and wave the flame over the weeds just enough to make their cells burst.
The weeds don't have to be aflame to be killed, just dried out.
I cant really gove you an answer,but what I can give you is a way to a solution, that is you have to find the anglde that you relate to or peaks your interest. A good paper is one that people get drawn into because it reaches them ln some way.As for me WW11 to me, I think of the holocaust and the effect it had on the survivors, their families and those who stood by and did nothing until it was too late.