Modern warfare in civ 3 can be quite a frustrating experience, since the gameplay changes entirely, but i have played games and found some unique ideas that work in Industrial and Modern age wars. At the begenning of the industrial age, Riflemen suddnely make a great deal of units obsolete and is the first unit that shows the signs that charging on cities will not work. One of my games I sent 10 Vetrean Riflemen into a city with 1 regular rifleman, I lost 7 of those riflemen and the 8th one was in the red. This can be irritating and can get people to say " this is bull@#$%, " but in reality this is extremely accurate because at this point its trench warfare, not open fields where you can send thousands against a few and still lose because of defenses. But what can be used against these kind of defenses? Cavalry are ok against Riflemen, but still have issues. When you get infantry, it gets much worse and only the tank will be able to defeat the Infantry regularly. The key for wars may be different, but most of the time it is for pure expansion. if that is the case, there are much better ways to wage a WW1 style war. Artillery pieces become probably your best tool, if not cavalry. Artillery can fire on roads and key recources while cavalry can rush past lines, pillaging all they see. Your opponent may see this and kill your cavalry and artillery despite guards, but these blows are worse and can get a country bankrupt really fast if used effectively. I played a game in the modern age when i stormed a enemy city with tanks(I had no cities nearby, i was passing through allied territory), only to load it with paratroopers and land all across theyre land (I had helicopters to lift them). Once helicopters are in the war and you have stormed an enemy city, you will have the upper hand by taking the opponents economy while yours is probably unthreatened. While wars can be controlled through these quick attacks and pillages on the enemy's economy, you still wont prove your point to the AI, (in play the world, I expect that a human player would want to surrender if they saw their economy sent straight to @#$%). How do you prove your point and take the " impenetrable " cities? Artillery and Air Raids are this answer, although air is a bit less effective for it (better for pillaging), they still help take enemy HP down then you can make a frontal attack while they are weak. As far as the navy is concerned, you probably wont have mass naval battles, and the ones you come across wont be against fortified bases, so you can ultimately prevail/lose a sea war, which can be a key for the war. on cross-continent wars the sea is the most important area of war. Your goal is to guard every transport you have going to the enemy shores, and to harrass enemy shores. On cross-continent invasions lots of people land theyre men as soon as they get there...BAD. you should wait until lyour whole force is collected for you to make a strike on an opponents shore, a quick landing can lead to bieng surrounded, your goals for the assault are to secure at least 1 city where you can ship in forces by loading it with units, then when resistance is gone, force building an airport, form there your true invasion can begin... Perhaps these quick tips can help some people in their quest to become a master of modern warfare in civ 3.