Taxes are much less likely to bankrupt millionaires than they are to destroy the lives of those living below the poverty line. Arguments have been made that the "American Dream" offers everyone the same opportunity, but this is simply not the case. People do not start on equal footing; people that come from means are born into means. People of varying races, genders, and classes struggle under the weight of far different obstacles to reach the top. Those with excess wealth and means should absolutely ease the burden of those struggling from paycheck to paycheck.
I believe that rich people should pay more taxes because, first of all, they have plenty enough money to go around. Secondly, It is the poor people that tend to pay more taxes. So if you put it into perspective, us, the poor people, are getting even poorer. And the big corporations are getting even bigger and richer.
Millionaires should pay their fair share of taxes--as a percentage of their income. Many of them pay very low percentages of their income and this is unfair to those who have less income and pay a higher percentage in taxes. This is where the addition of a flat tax might be helpful.
Millionaires, in most cases, have earned their money or inherited it. Why should they be penalized because they have more than someone else. Taxes should be based on a percentage of income or earnings and there should be a cap of 35%. Taxation higher than that would be unfair to those fortunate enough to be making more money.