Would this be fun or tedious?

That would be entirely dependant on how you implement it.

Developing a game that premised itself in part on destroying supply lines would mean developing economies for the armies i.e. food, drink, ammunition, parts, medical supplies, new recruits/reinforcements etc. so part of your game will be focussed on the development and supply of those materials to your armies just as the enemies themselves would need to develop them. Dependant on the scale you do this it might come down to armies being supplied by a number of different towns/cities and differing types of goods in the supply trains for example a small town might supply you with new recruits and food whereas a city might provide you with new recruits and ammunition etc etc.

In sabotaging enemy supply lines you would also need to give consideration as to how you will maintain your own strike force with supplies whilst they are in enemy territory which might lead to such areas as brigandage, pillaging of enemy supply trains, sacking of small towns. It may even lead to such things as razing and salting the earth to deny future supplies to the enemy army. Conversely this would mean defending your own zones of control from similar tactics made by your enemies.

There are many other issues and ideas that could be suggested to expand upon your initial post, but I would want to see more development of your idea above from you. As a game it could be quite fun but as I said at the start it truly depends on how you implement this game with regard design, gameplay etc.

Hope this helps :)

What is there was a strategy game with logistics? The armies would need food or ammo or whatever else to stay alive or be able to fight. Supply trains would get their materials from a town controlled by their player and move out to their army. Other armies could attempt to cut the train off to weaken the other. Would this be fun or tedious?

The single best (to my knowledge) implementation of logistics in a strategy game was in Gary Grigby's War in the Pacific. While land supply was a little abstracted, supplies were otherwise loaded onto ships which could be attacked by land based air units, subs, etc. In fact, WITP has been called a logistic simulator with a combat engine tacked on, but that models the actual war pretty well, too.

The big problem I see with having an excessive emphasis on logistics is that it can add a lot of cruft without really enriching the player's experience. It can also be a technical challenge to make the AI decide to load up a truck and send it out to the troops. In practice, it seems like the most common solution is just to allow units to track back a supply line to a friendly base or area. Hearts of Iron modifies this by the infrastructure the supply line has to travel through -- bad roads = crappy supply.

OTOH, it might be interesting to see a game modeled around trying to supply an army and let the fighting be relatively abstract. Given the problems that the Allies had with supplying their troops after Overlord, it would be an interesting challenge to simulate the Red Ball Express. Maybe call the game Beans, Bandages, and Bullets...start off with a small tutorial like providing supply to the U.S. Army during the Louisiana Manuevers and work through scenarios like trying to supply the 6th Army during Stalingrad and so on. You would have to plan ahead and request supplies based on what the war situation was looking like, too -- a defensive battle would mean lots of ammo and whatnot, while an offensive battle would need fuel and soldiers.

Considering that plenty of people like city builders and other economy games I don't see why logistics would be a huge problem. Raiding caravans was plenty fun in Majesty and other games has similar stuff.

I have often started to design games in this category, although as some of the previous replies say, is it really fun? My personal opinion is that it should be doable. You really need to find fun aspects of the logistics so it's as fun as conquering enemy territory. Making supply visual and semi-automatic could be one way ahead. Instead of moving lorries, you could setup setup supply routes. There should probably be routes generated for you so all you need to do is tweak them. That way it can be reused for the AI.

Some examples of games with different logistics:

- Colonization - You spend much of the game moving different cargo. This is one of my all time favorites (although not the remake...)

- Battle Isle series - Having special units that can refill your combat units.

I would try Warrior kings. There was not much in the way of logistics bit it was a great game. The premise is that archers had a limited supply of arrows (meaning an army had to have a supply wagon which also doubled as a medical wagon) and each village you created was a hub where reasources were stockpiled and had to be sent to your castle with carts. These mechanics added depth to the game but it was still accessable. The relience on supply wagons also mean that large armies were more common than tiny ones as you get in some strategy games.