In my opinion the context of Paul in his letter probably written for his new non Jewish audience was about what to do now that we are Christian? Does our freedom in Christ, or maybe even our very Christian nature allow us to challenge the secular government of the day. As we see in many ways it does as the apostles along with Paul broke the law. They refused to obey Cesar continued to spread the gospel despite the law. For such acts they were punished, but they were not shamed, but proud. I believe Paul wanted the converts to be good Romans to not break moral or natural law, because within that one finds peace and freedom from those who enforce the law. But at times when practicing and preaching the gospel our authority in Christ allows us to fight the law just as Jesus who healed on the sabbath. Just as the believers in Scripture as well as our modern missionaries in lands in which Christianity is forbidden, and yes in America when injustice is taking place. Also I may add our very constitution allows within the law the right to protest it even goes so far to speak of dismantling the government if it starts to fail. We are not in Rome under Roman authorities. Remember even Jesus destroyed property in the name of justice.