The president has spoken at length recently, and throughout his Presidency, about the need to raise revenues by taxing the "millionaires and billionaires." In the paragraphs that follow, I'd like to point out a few things that make this statement much more complicated than the President implies.
Simply enough, a millionaire is someone whose Net Worth is $1 Million or more. Net Worth is a function of your Assets (things of value: cash, stocks, property, business ownership) less your Liabilities (debts, mortgages). If you have a million dollars cash and no debt, you are a millionaire.
When you look at an individual tax return, however, at no point does the Form 1040 ask about your balance sheet. The form is blind to the value of your assets or the sum of your debts. It only cares about your Income. Assets and Income are related, yet far from the same thing. From the example above, you have a million in assets but if it's all sitting in stacks of cash under your mattress you have $0 in taxable income. If your million is in a bank savings account earning 1%, your taxable income would be $10,000 (prior to any exemptions or deductions allowed by the tax code).
On the flip side, some tax returns might show huge amounts of income without any net worth at all. It's possible for an individual to have $1,000,000 in taxable income without having a penny to their name. This happens because taxable income is not necessarily equal to the amount of cash coming in. If someone forgives your debt, you may have taxable income, but you did not receive cash. Also a person might make a million, but has no Net Worth either through large borrowing or lavish spending. This person is not a millionaire per our definition above, but shows a high taxable income.
So whose taxes does the President want to raise, the high earners with no net worth? What about the people who have a million in the bank through savings and frugality but still only make 75K a year, surely it's not right for them pay taxes at an elevated rate.
I guess the point I'm trying to make is that we shouldn't carelessly throw around terms like "millionaires and billionaires" without thinking about what the words actually mean. And after thinking about it, I'm not exactly sure whose taxes President Obama is hoping to raise.