What do frederick douglass' words "america reigns without a rival" mean?

Frederick Douglass is a world-wide known man. He is known for his amazing quotes, whether he knew they were quotes or not. His words, "America reigns without a rival" means "We fight for the rights as citizens" or "We take pity upon our dear souls regardless of ones' actions." 
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Think about the abolitionists movement. Fredrick Douglas escaped slavery on a train with everything he had. He was very articulate and very well educated and was liked by many people. But what he meant was, in order to win, we need to take what's rightfully ours. (Freedom) hope that helped!