I like the way you cleverly use contrived examples. In my field, we call that "lack of charity" towards the opposing view. We also call it sophistry.
The Principle of Charity is basically that the best argument is the one that defeats the strongest version of the opponent's view. If you have to come up with an idiotic version, you haven't successfully argued against anything but that version. So it is in your
best interests to concern yourself with a a position that assumes the opponent is not an idiot.
Further, I should point out that counterexamples don't prove much in the case of general principles. The idea of principles is that they are held in part because of the
overall effect they have. Of course there will be cases where principles will be tough, but that is true as much for conservative views as liberal ones.
Now, some specific rebuttals...
1. How many criminals can get away with this? If it did happen, one solution to this is tigher security in the prison. Killing the guy isn't the only answer. Sure he's scum, but to kill is wrong-- even when killing a killer.
2. The intruder... I have only twice had someone break into a home I lived in, in 24 years. In neither case was my life in danger. I feel that had there been a gun in our home, I would have been in more danger. Further, I refer you once again to my statement on principles. I don't dislike people having guns because of *my life*, I dislike them because it gives people the power to *kill*.
3. You should note, first, that many liberals are anti-abortion. You can be pro-choice and anti-abortion. If my cousin (I don't have a sister), or girlfriend, or someone close to me wanted to have an abortion, I would advise her strongly not to. I don't think it is right. However, whether a fetus is alive is a slippery slope, and I don't think the government or right-wing Christains should have the power to decide when its murder and when it's birth control. Freedom of choice, because we can't be sure it's alive, and it sure as hell seems like it isn't. Plus, had my mother had an abortion, I would never have been born. Would not bother me any more than if she had used a better brand of condom.
4. I believe in a less powerful federal government. Liberal does not equal Democrat. Do not assume that because in the US, the major liberal party wants large government and the major conservative party wants small government, that left-right equates with libertarian-federalist. It does not, it is just a coincidence.
5. Doctors are there to save lives. All a gun is designed for is ending one. How many lives to guns save, versus doctors? I am guessing your numbers don't stand up so well if you use both positive and negative results of each. That is, assuming they are accurate numbers... statistics can be misleading.
How's that?