There is no doubt that Nehemiah knew that he was going to face opposition to his plan for Jerusalem. There were those who were making a living off of the Jews pitiful situtation there. He knew they were going to be mad about losing their livelyhood and that they were going to do everything they could to stop him.
In chapter 3 we begin with Step 1: Insult with influence. We've all been insulted at one time or another. Nehemiah's enemies use all the influence they have to intimidate. Nehemiah refused to be intimidated. Fear is a powerful motivator and when we choose to live in faith and not in fear, we will conquer step 1. Nehemiah's response prayer. "Lord let them reap what they sow."
Step 2: Make plans to attack and destory. Now remember this, "they are making plans" Again here fear is the motivator. The attack is real, but it hasn't happened yet. Nehemiah's plan, Pray again and raise up guards against the threat. When your enemy knows that they are in for a fight, most of the time they will back off. They are just as afraid of losing as you might be.
Remember that God is in the midst of your plans. That He promised to fight your battles for you. Even if sparks are going to fly, God will be there too!
What happened? In verse 15 their enemies were frustrated and could not fulfill their plans. There were not conquered! That wasn't the goal. The only way Jerusalem was going to conquer their enemies was to finish the wall and rebuild the gates. Be prepared!