how to prevent ai cheating in Anno 1404?

even easy ai starts with stone and the big church and seems they have infinite resource ,even if i cheat and get my ship to immortal and bombard their base they just rebuild with no penalty

also yesterday i bought the grappling hook and big ship from Al Said,and attacked the stupid blonde easy ai guy,and it show 2 shields on the ships and he suddenly captured mine for some reason and stole it