Hang on there.
Capital gains have been taxed differently from regular income for over a century (since 1922). In fact, from 1954-1967 capital gains rates topped out at 25%, while they were re-set to 28% in 1987.
Think about it for a moment. If you bought a house in 1990 for $100K, and today you sell it for $350K, have you really earned any actual value? No, of course not - the "gain" isn't really a profit, it's just a reflection of inflation. If you take that $350K down the street to buy another house, it isn't going to buy anything larger or in better condition that what you sold, there is no actual "gain" from the transaction. Why should it be taxed at all?
Wolters Kluwer takes a historical look at capital gains rates in the United States.
www.wolterskluwer.com