Buy alot of industrial tech and keep getting more land. Full deffense is bad for communists ; You only have 1 thing to sell at the market, thus leaving u exposed to market idiots who put stuff too cheap. Also you need to get fat for this strategy to be good. Most players like to get on top fast and get land aggressively until most players can't retal them. At that time its easy picking, you can get 4k land a day.

Your bpt's efficiency peaks at 10k acres.

Also, if you want my advice, somebody attacks you you missile him :P.