I don't know if there will be a world war, there may be a huge war but I don't think it will be like the other world wars, I doubt a country will set out to conquer the world, however I am sure some country will push their boundaries and get shot down. If any country in the UN does something incredibly stupid in complete defiance of every nation in the UN, then something may happen involving multiple countries but I think we are going to have a war between maybe two countries with other countries sending support, such as China vs. USA with USA getting UN support and China getting NK support, I doubt China will rise and try to seize all of Asia for lebensraum.