Do you think there should be a flat or progressive income tax (for the US)?
In principle I like the idea of a flat tax. I don't see why people should pay a higher percentage just because their income increases.
The problem with any system of taxation is that as soon as tax exemptions are allowed you create loopholes. Corporations typically deduct operating costs before income is taxed, while individuals usually don't get to do that sort of thing. Which makes it advantageous to create some kind of corporate structure and route as many expenses through it as you can get away with.
In many ways the issue of a flat or progressive tax structure is secondary to making tax easy to understand, easy to calculate, and difficult to avoid. A large part of the problem is the cost of compliance with tax law, especially if you find you get something small but unexpected that has to be declared. Some years ago my wife received an unexpected payment as a result of an inheritance - it was only a whisker over $10 but it took half an hour to figure out how to declare it on her tax return. It would have been easier if there had been a way to say to the IRS, "I got this $10 unexpectedly - here, take all of it" and not bothered with the forms.
