Since rebels can take over your base in Algeria, how about the end of the world? Right now, game worlds abrupty end at a preplanned time. Why not say DOTM will go through 2010 at a minimum and 2030 at a maximum and then have an end of the world event? Right now everyone stops ordering planes etc once the end is near and basically stop playing. If the end of the world happened in 2015, there would be people still playing, putting in order, expanding, opening bases, etc. People will start ordering those 787s because they have no idea how long the game will go on and could get a solid 20+ years out of them.
If you do this, I'm expecting something epic: Nuclear Holocaust, Bieber Fever wiping out the population, Four Horsemen, etc.