I stumbled on a good series of articles about the recent trends in U.S. tax policy over at Newsweek: Why Your Tax Cut Doesn’t Add Up: Behind the promises to save you money, a hidden agenda is at work, with a stealth tax to pay for it all. The gist of it is that the “income” tax has become a “salary” tax, with other forms of income (such as inheritance and investment income) escaping taxes. This shifts the tax burden to folks who have to work for a living, which, as we computer science types like to say, is “not a bug, it’s a feature!”
Another article, from Reuters, provides some details of how corporate income taxes have dwindled over the years: