Taxing the rich brings the fear of recession to the masses.

To some extent, super wealthy people, especially entrepreneurs, have the rest of society over the barrel as most of the rest of society values consumption and prosperity as well. It's true, to some extent, that taxing the rich can slow the economy, or in the case of state taxes, it can cause the wealthy to move out of state. Politicians often back down on taxes as the prospect of a slower economy is feared.

In the long run, sometimes higher taxes and more investments in things like infrastructure and education can add to wealth, but that is more of a long term effect. When people think in the short term, fear of recession hits so they often back away from taxing the rich.

The rich and the corporations are one of the backbones for our type of society.