I've been toying with the idea of creating a modern war RPG, with modern armies such as America, China, Britain, and smaller ones such as South Africa and Cuba. Any state could join in. But I need a big bit of help. Maybe some of you would be interested?

I could probably help you with some of the technical and economic aspects needed.

i will join if it has enought peeps to be interesting.. I GET DIBS ON BRITAIN :p

Is modern Japan usable?

Yes, but it will be neutral until RP'd otherwise.

Japan would get owned by itself.

terrorists... do terrorists get mentioned?

Middle Eastern Coalition. MEC. Terroists.

And I imagine the IJN would send the entire Chinese fleet to the bottom of the ocean before it gets overrun. And a good bit of the Chinese air force would be blown out of the air. And a lot of Chinese infantry battalions would get their butts handed to them.

At the rate they could pump out tanks? No way.
I take it there's no such thing as nukes in this RPG so that you could successfully prevent the lack of military action due to threat of them as in real life.

Good luck getting those tanks across the water to Japanese soil with the entire Chinese fleet on the bottom of the sea.