What does "Drum" by Linda Hogan mean?

The drum is the symbol of the Native American heart. It beats on literally in the womb when the unborn child is still inside its mother, and it beats on figuratively in the world, providing an insistent undertone, a rhythmic accompaniment to the unfolding history of Native Americans. The drum represents the continuity of the community, its inner strength undiminished and unconquered by years of exploitation, hunger, death, and the systematic theft of tribal lands.
And what gives Native American tribes their inner strength? Their unity with the natural world around them, a oneness with the soil that keeps them rooted to the land despite the endless trials and tribulations they have endured and continue to endure. The Native American spirit, however, originated in the water before it came to the land. That is where its heart truly lies. And the spiritual life of Native Americans takes them back to the sea, allowing them to recover the memory of water. A return to the water is a return to the safety and comfort of the womb, where the spirit rests peacefully to the beat of the drum.