The domain name system (DNS) grew to prominence during the early, innocent days of the Internet. During that time, Reagan-era users tended to work for government or educational organizations where trust was assumed and security was an afterthought. Since the online community was small and the Internet was sparsely used, the importance of DNS was not widely understood, and as a consequence, left undefended.
Fast-forward to today and you can see the resulting problems: criminals who redirect DNS queries to their own servers to steal credit card data and other sensitive information. There's also the exploding problem of distributed denial of service (DDoS) attacks, often aimed at DNS to cripple online business. For businesses, the stakes are simple: no functioning DNS, no website or Internet presence.