Then you have five symbols:
. Freedom/ independence (darkblue)
. Peace/ harmony (white and dove)
. Active defence (shield)
. Security (lock)
. Privacy/ unseenedness (black)
I personally associate freedom with white because its like a piece of unpainted paper. I associate peace with green because it is the color of plants which symbolizes nature.
If I understand security, it is a contrast to the active defence in that it is passive defence. If so, you could possibly play around with how these symbolically relate to each other. For deem looking at them as a two sided unity.
You could do a tricolor of black, green and white and have a shield and lock/key in the style of the communist flag.