You likely want to start, or continue, to develop ways to bring in additional income. If you are new, that amount of cash might have been largely brought about by beginner's bonuses. If you haven't already, review your finance page and identify how you currently bring in income and whether beginner's bonus continues to be a part of it. Further, look into if you were to spend that 4T, how you would make your next 4T, or more.
Being in the FB forum, I would assume war is an eventual goal. I don't advise starting on that world but, otherwise, a rough path to advance can be found here:
https://www.simcountry.com/discus/messages/16295/25064.html?1440190635