Gun violence is a public health and safety issue that is largely unregulated. According to an article in the Journal of the American Medical Association, US taxpayers paid over $1 billion in a single year for gun-related injuries (
http://jama.jamanetwork.com/article.aspx?articleid=191001). Liability insurance on guns will hold gun owners accountable for the proper use of their guns, while protecting the public and lowering health care-related costs for everyone. It will encourage gun sellers to sell only to responsible people, thereby reducing their own risk. Courts will see it is in their "compelling interest" (and, therefore, constitutional) to make it mandatory. There are many legal precedents for liability insurance. Fully privatized underwriters will offer lower rates to responsible gun owners. Insurance companies will appreciate the new source of profits. This is a win-win proposition.