Romans 13 has long been abused. One side uses it to justify injustice propagated by the government while activists generally ignore it. Richard Horsley and others have made a strong, albeit not watertight, argument that Paul is carefully straddling a line during a critical time for the early church. It is important to remember that Paul is indeed executed as an enemy of the state but it is also important to remember that he willingly submitted to the execution even though the charged were bogus (all this depends on whether church tradition is right that Paul was executed by Nero as a part of his scapegoating of Christians for the burning of Rome). It would appear that a follower of Christ but humbly and prayerfully seek a balance between Romans 13 and Acts 5:29).
What is more interesting to me on the eve of my next sermon is that chapters 12-13 are punctuated by the reminder that the hour is late and that our King could soon call any or all of us to account. Paul did not shy away from reminding his churches to walk in the shadow of judgment. Paul was not a televangelist with a pants cranked up to his armpits and a wife with big hair and so much make-up that she looks like she lost a paint ball battle but "the end" (whether personal or corporate) is an issue that Jesus' chosen instrument believed was an important way to keep our depravity in check.