Modern countries have data for which other countries they border by land. Users with sufficient access can use "armies" they gain every 24 hours to "occupy" countries, attack and defend them from other users.
Armies are gained by going to one of these country pages 24 hours or more since they last earned armies this way. The number of armies earned is 2+(#countries/3 rounded up).
If you have no countries, you can take over an unoccupied one with only a 10% chance of losing one army. Or you can try to incite rebellion on an occupied country with a 10% chance to remove an occupying army per unplaced army.
You may attack a neighboring occupied country if you have more than one army in your country. Each attacking army has a 45% chance of killing a defending army, otherwise the attacking army is killed. This continues until one side loses all armies.
You may move your armies between any neighboring countries you control. 1 army must stay on any country you control, you may move any number of additional armies you wish.
You can disband your armies on a country. By doing this you will lose all those armies.
If you have 5 or more unplaced armies and a country with a water border, you can build a Port on that Country/Water border for a cost of 5 unplaced armies.
Once you have a Port, you can build cruisers at that port for a cost of 4 unplaced armies. Cruisers can carry up to 5 armies to attack countries across water.
For a cost of 5 unplaced armies, a country may initiate nuclear research. 3 days later, that country may build a nuclear ICBM for a cost of 15 unplaced armies, which takes 2 days. A nuclear ICBM may be launched at any country on the board, will destroy all armies on that country, and will render the country uninhabitable/impassable for one week.
If you own Panama, you may move cruisers from the Caribbean to the North Pacific or vice-versa through the Panama Canal.
If you own Egypt, you may move cruisers from the Mediterranean to the Red Sea or vice-versa through the Suez Canal.
Link to States/Provinces level game [Link]
(Warning - very big map files will load)