Animals in the circus endure deplorable living conditions, are subjected to cruel and abusive training techniques, and experience measurable biological trauma by living an unnatural circus life. The welfare of animals in the circus is an absolute black eye for humanity in the 21st century, and needs to be addressed once and for all.
The United States should pass legislation requiring animal-free circuses. Countries like Bolivia (2009) and Greece (2012) have already passed laws banning the use of animals in the circus, and several other countries worldwide are considering the same. Many sanctuaries exist in the US for housing retired circus animals, and would be glad to provide a proper home.
See http://tinyurl.com/cfemno for scientific research on the welfare of circus animals.