Hi!
Welcome to the game.
While you can never be fully defended, there are steps to better protect yourself.
Join a nation (ZA is training new players, feel free to put in a request to join)
Keep a few thousand spies on you at all time. You do not need millions at this point in the game, but 50k-200k will work nicely.
Depending on your nation, they are supporting Tanks or Infantry. Make sure you have a lot of these units on hand. They will be the bulk of your defenses.
Nations
[usa] x 48[wlf] x 8 [want] x 3 [tng] x 1 [NS] x 8 [px] x
1 [HuuF] x 1