Control-click on a country to display a contextual menu with options for that country. At the top, the menu shows the name of the country and the player who owns it.
If you are placing armies, the Place Armies submenu allows you to place a specified number of armies in the country:
If you are attacking, the Attack submenu allows you attack a specified number of times:
You can also choose Cards, Fortify, Done, New Game, or Statistics from the contextual menu. In addition, you can start a new game from the iConquer dock menu: