Hearts of Iron II

[discovery1]

Another tip: if an invasion is too strong too resist, let them land and retreate your troops to the aeas on the flanks of the landing zone and leave a path inland open. When they advance they will weaken their defences and leave them open to counter attack. Then you cut them off from their supplies and kill them at your leisure. The ai may be dumb enough to fall for this, although I haven't tried it yet. Also disband your fleet on day one. It is completely worthless as you found out to your cost.