"I urge, then, first of all, that petitions, prayers, intercession and thanksgiving be made for all people--for kings and all those in authority, that we may live peaceful and quiet lives in all godliness and holiness." (1 Timothy 2:1-2)
Do you pray for your leaders in government as much as you complain about them? In fact, we should pray, instead of complaining. Every time you're tempted to complain about them, pause to pray for them. God wants us to pray for all people, even those whom we disagree with. "Paul's command to pray for kings was remarkable considering that Nero, a notoriously cruel ruler, was emperor at this time (A.D. 54-68). When Paul wrote this letter, persecution was a growing threat to believers. Later, when Nero needed a scapegoat for the great fire that destroyed much of Rome in A.D. 64, he blamed the Roman Christians so as to take the focus off himself. Then persecution erupted throughout the Roman empire. Not only were Christians denied certain privileges in society, some were even publicly butchered, burned, or fed to animals." (commentary from Life Application Study Bible) This shows that we should pray for evil leaders as well as good leaders.
The purpose is that believers may lead a quiet and peaceful life (this doesn't mean compromising your moral standards/Biblical principles), which is instrumental to the greater purpose of bringing the Gospel of salvation to all people. Not all will be saved but salvation by grace through faith in Christ is offered to all. We must remember to pray for all people, including unbelievers.... yes, even the ISIS. God desires that through the Church's witness, all people may be saved and may come to the knowledge of the truth (verse 3-4). When we choose to honor God and His Word by obeying Him even when it's difficult and/or unpopular or even when we don't feel like it, the world will take notice and we will have an opportunity to point them to God. Be a light in this world of darkness. Be a reflection of Christ. Display the love and grace of God for all to see/experience.