I'm new to this game, so after playing through all the tutorials, I thought I'd start with a simple 10 planet map and an easy AI level. Either I'm completely useless, or missing something, as I can't seem to do anything to progress here.
There are two clusters of five planets. From my starting planet, I could see one heavily defended Mark III planet to the west, and one more promising target to the north. I captured the one to the north, then the next one immediately adjacent to that which was slightly better defended, but had an advanced factory on it.
The next planet on the path was another Mark III, so I turned my attention back to the first one, bordering my home planet. That one is the gateway to the second cluster, so I must either pass through it, or defeat it. Passing through never got me very far - on one occasion I managed to briefly get a couple of ships through to the next planet, which turned out to be an AI homeworld.
So, as I see it, the only option is to attack the Mark III. It had one special forces guard post, and I think three other guard posts, along with an astro-train station. I killed the special forces post, and two of the other guard posts, but the third has a force field on it. Almost every ship was Mark V.
I've built up the largest fleet I can manage (300 bombers, 275 fighters of mark I and II, and 300 microfighters of II and III), along with a flagship. They are all sitting inside the hostile system, at a turreted beachead that I can defend.
I still can't send the fleet to take down the force field before the fleet is wiped out. I can't take out the defences around the wormhole to the AI homeworld without being wiped out. If I free the AI by dinging the command post, they overwhelm my defences and I'm wiped out. (I tried also building all turrets allowed by the cap at the beachead, still got wiped out).
Nuking doesn't work as there are about 2000 Mark V ships which survive the nuke, then wipe me out.
I'm just about completely out of ideas here. Is this map now unwinnable? Did I do something wrong to start with? This was supposed to be an easy starter campaign!