0
I think:
1. Write brilliant and catchy dialogues, never use stereotipated phrases and don't underestimate the power of words. (and how they are spoken!)
2. Don't force yourself. If you can't have a brilliant idea for a politic movie, don't talk about politics in the movie.
If you want to make a movie about war just because everybody seems interested, don't do it unless you have something different to say.. well, don't do it!
(then, if your mind tells you something that could change people's take on things, try but, once again, don't force yourself)
3. Don't write with the intention of shocking, if there is something 'strange' like gay characters, perversion, adultery.. don't make it look like a sin or something to be afraid of.
Let it happen! Who gives a damn about fake moralism right now ? We are in 2006.