Interesting that you bring up "theft by taking," as it relates to the death tax. I agree wholeheartedly. Additionally, in his book "TAKINGS," Richard A. Epstein, Constitutional Law Scholar at the University of Chicaco, suggests that the progressive income tax is likewise an unconstitutional "Taking."
You see a person with a nice iPod. Would you turn to your friend and say, "I like that iPod. Would you please use your gun and take it away from that person and give it to me?"
Of course not. But what is the difference between that and what the government does every day - at the point of a gun, by the way.