What do you think of a national retail sales tax?

[Berzerker]

UR - The same as when liberals seek to oppress the rich in the name of helping the poor, express my opposition at the ballot box until it becomes legal to shoot the tax man.

[Ramo]

Am I "oppressing" a would-be murderer if I defend myself? If not, then it's not "force" that is oppressive, but the initiation of force, true?

On second thought, "oppression" isn't an apt word as it has necessarily negative connotations. Pretend I used "authoritarian" instead of "oppressive" instead.

But no, I don't agree. I don't see the distinction between the initiation of force and non-initiated force as important. If you hit me and go home, and then I hit you, my action is not morally superior to yours despite you initiating force.

What I see as important is the distinction between a greater force and a lesser force. Forcing a person not to hurt/kill you is a smaller constraint than forcing a person to be hurt/killed.

Authority is not the problem, mis-placed authority is the problem.

Well, yes, that's what I'm saying. But authority is justified if and only if it ultimately minimizes authority.

We all have the authority to defend ourselves from attack,

Not really. If someone is stronger than me (and everyone willing and able to protect me), I don't have the authority to defend myself.

therefore government, on our behalf, has that authority.

Are you saying that you think governments have you moral right to throw people into prisons - taking away all their freedoms - because you think everyone has the moral right to defend themselves? You'll have to explain that one.

If I steal Sava's computer, does he have the moral right to steal your car?

And how does the use of force to compel a rich or poor person to hand over their money - taxes, progressive or not - reduce this "net authority" if that person is using no force (authority) against others?

I would say that there aren't any people who have no authority over anone else. But reasonable police and prisons, welfare programs, and the like can reduce more authority than it takes to fund them.

[Urban Ranger]

The problem here is there are a lot more poor people than rich people. Hence, Libertarianism is not a liberator, rather, an oppressor.