When it comes to fighting, Christians are to be lousy tacticians.
I mean, let's say I have an enemy. My old sinful flesh knows how to handle this. If you can, simple overwhelming force is the best - just force them into submission, where they acknowledge your superiority. Mental, Professional, Superior Office - whatever. Just silence them.
And if that option isn't available, my old sinful flesh knows the next option. Outflank them. Attack obliquely. Don't deal with them directly, but attack the sides. Tar them a bit. Insult them to the people who know them, or even those who they might come across. Wear down their power base, their support structure.
And of course, tactics are all about deception. So my old sinful flesh knows what to do. Make mountains out of molehills (all in the name of the "truth"). Pull things out of context and harp on them. Even, if it will hold, outright lie.
That is how one wins a fight, at least according to the ways of the world.
Yet that is not what we are instructed to do in the Scriptures.
Christ tells us to love our enemies and do good to them.
We get the same thing from Paul.
We see David doing the same thing to Saul when God gives Saul over unto David's hand.
No, when it comes to "fighting" - to dealing with one's enemies, Christians are to serve them, endure up under them, show mercy, forgive them. Yes - be resolute. Yes - maintain the truth. But still... show kindness and gentleness and self-control and all those other fruits of the Spirit unto them.
But - then again... what would I know? I'm an antinomian disdainer of virtue and sanctification, don't you know =o)
Never dehumanize your opponent - for to do so is a denial of Christ Jesus, the God who doesn't dehumanize but instead becomes Man to win forgiveness even for them by taking their sins up upon the Cross. There really are no enemies - there are only those who tragically are still trapped in their sins. God be merciful to me, the sinner!