In the near future, military will be small, cheap (relative to stealth bombers, which isn't saying much), and remote. The people that brought up the U.S. Predator are on the right track. However, no war will every be brought to a conclusion without boots on the ground. Units in the future era of CIV should eventually have extraordinary bombard and recon range. But tanks will hardly improve.
Here's an interesting wrinkle: Space based weapons are not fantasy, but don't expect them to shoot lasers to earth. More likely they will take out our enemies spy and communication satellites. Unfortunately this will also create a shell of shrapnel moving at 26,000 miles per hour orbiting the earth and will make it impossible for anyone to lauch anything into orbit or beyond. A microscopic piece of paint moving that fast can punch a hole in the walls of spacecraft. Should a space war break out in future civ, all spaceship parts will be shredded and no one can build and launch spacecraft until they build an "orbital cleanup satellite wonder."