If you fill out the forms and send it to the IRS and it says you OWE and you don't pay, of course they won't throw you in prison, you have already admitted that you owe them by filing your tax forms. I guess we are talking semantics here, but if you make income and have taxes due and don't file your taxes, you will go to jail. Fraud on your tax forms is illegal, not because you aren't paying your taxes, but because FRAUD is illegal.
So that $40K you owed them, you never paid and they never did anything about it? So I assume you never pay your taxes then, is that correct?
I think people may have a misunderstanding of what a slaves life was like 200 years ago in the US. Sure, for some it wasn't a good life at all, but for some slaves life was actually pretty good. Do some research on how slaves lived and some of their own thoughts and you will find it wasn't daily beatings and rapes and 20 hour work days 7 days a week. Some slaves actually enjoyed themselves very much and didn't even consider themselves a slave, but more like a privileged black person with a benefactor. Some slaves were sent to University and were given homes for them selves and their families. Slave life for all was not just like a episode of Roots or anything. And just like you don't consider paying 1/3 of your labor to government as slavery, those slaves that were well treated didn't really consider themselves as slaves either.