Tropico 4 is a political and economical strategy game. I guess it can be defined as a real-time strategy game, but without all the war elements. In Tropico, you play the role of "El Presidente". You have to manage an island nation, which resembles Cuba. El Presidente shares the name of Fidel Castro, too. In the game, you have to make your citizens happy while tending to all the needs of your nation. You have to co-exist with 8 different factions, including the Religious, Communists, Capitalists, etc. You also have to make sure that the world powers like you. If one of the two major powers (US and URSS) doesn't like you too much, there is the chance that they might invade you. To keep people, factions and world powers happy, you have to complete tasks. For example, the Religious factions always ask for you to build churches. If you do it, they are more loyal to you, and they will support you if there are elections.
The game has a nice tutorial that explains pretty well what the game is all about and how to play it. I finished it in less than half an hour, and I gained a lot of insight into how this game is different than most strategy games. It is not a fast paced game; not at all. There are tons of things that you have to take care of. But the game proves to be rewarding.