Not a PC game, but it looks pretty intense due to recent events over in N.Korea. Has received excellent reviews as well. I just pre-ordered the reprint.

I think this would be pretty interesting play through with different scenarios.

http://www.gmtgames.com/p-537-next-war-korea-reprint-ed.aspx
https://boardgamegeek.com/boardgame/69130/next-war-korea

I have it (along with all the others in the "Next War" series) and all are great games. I believe "Next War: Poland" is the the new game that has yet to be released.