Responsive design for a government website, means, among other things, that it must be handicap-accessible and conform to screenreader guidelines, be viewable on browsers of constituents who may not have purchased a computer in the past decade (i.e., IE6), and also compatible with modern browsers.

This is a lot of work, especially making a website that is screenreader-accessible or works in IE6. You don't get to just abandon those visitors, like so many websites do today. Those people have just as much a right to access a functional government web page as people using modern browsers.