Making everybody subject to the income tax is not about raising the tax burden. If everyone is subject to the income tax, then those who now pay nothing will suddenly care about how much Congress spends, and what income tax rates are. More people will likely vote for lower spending and lower tax rates. So, the ultimate result (naturally with a time lag) will be lower government spending and lower taxes.
That was the argument that I used to use, now all I hear is that increasing taxes is now universal, like so many things, the republicans and the democrats have combined efforts to figure out how to raise taxes.