Imo it depends on if you spawn in a decent pocket or not and how good the choke points are.

Also Rampant has a sibling weapons mod. Use it, it's awesome.

Last time I pulled it off, I spawned on an annatolia-shaped peninsula (including the straights) and managed to thread the needle with my pollution to get it walled off and supplied with bullet by train before my pollution reached their bases.

Added lasers, napalm flamethrowers, HE missles, and really aggressive repaire/maintenance as I advanced through the game. Never expanded past my initial defense line until I was mass-producing nuclear artillery.

You don't want to know how many times I had to reroll to get this map lol.