"For the weapons of our warfare are not carnal, BUT mighty through God..."(Read this scripture in its entirety here)
There is a reason why the writer chose to use the word mighty instead of a word that our society would consider an antonym to the word carnal, which might include the word spiritual.
So why use mighty instead of spiritual?
Perhaps the reason being is that Paul wanted us to see that carnal weapons do not produce the extent of victory that spiritual weapons do indeed produce. In this case, carnal weapons are the opposite of mighty weapons; they are not mighty at all.
If you can reach the heart and mind of a murderer and change his inward views, he will be changed and will ultimately make his own decision against killing people. He will not desire to kill, so he will not kill. But when you outwardly restrict the murderer -- perhaps by binding him up or physically disabling him or even institutionalizing him, it will only stop his hands -- not his heart. He will kill again, once he is free.
Spiritual weapons (i.e. PRAYER) change the heart, the mind -- the spirit and soul of a man. If the soul of a man constantly submits to God and his spirit is changed by God, this can stop killings, hatred, wars, and all types of havoc in our lives so that battles never even begin.
What battles are you currently facing that require utilizing spiritual weapons to bring about true and lasting change? (perhaps in a situation, a person or entire nation? perhaps even in yourself?)