the money that the TOP billion pay is a lot. However, raising it on them will not bring in that much money. What is needed is for ALL OF US that are above poverty, to pay taxes. 
Now, am I suggesting that the wealthy should get tax cuts or not pay taxes? Nope. 
Im suggesting that EVERYBODY should pay a FAIR TAX. 
A fair tax is one in which EVERYBODY that makes 100K, no matter how, pays the same tax. 
No deductions, no breaks, no exemptions. 
Just a simple low tax. 
Keep it progressive. 
Start it at 1% on everything about 30K (or whatever is livable money). Then cap it at say 25%. It could go up as high as 30%, but I think that 25% is probably a decent compromise.