A controversial topic...

Abortion.
I'm pro-life. Just so you know. This means that I'm about the preservation of life. So in extreme cases (such as the mother will die unless the baby is aborted) abortion may be necessary. Doesn't make it right though.
I'm gonna attempt to refute some of the most common arguments for abortion, or pro-choice. Let's start with what I think is the most common one:

IT"S MY BODY.

Yeah, there's a problem with that. It isn't.
This argument is a particularly selfish and ignorant one. The life form living inside you is not you. When a woman is pregnant, is she considered to have four arms and four legs? No. Two brains? No. Two hearts? No. So if the baby were apart of the mother, then she should be considered to have twice as much of everything. But she isn't.
Secondly, each part of one's body has the same genetic code. If the baby were a part of the mother, it should have the same genetic code. But surprise, surprise, it doesn't. Same for the blood type. In most cases, the type of the child and the mother of different. A body cannot function with more than one blood type, therefore, if the baby was a part of the mother, it would have the same type. But it doesn't, ergo, the baby isn't you.
Here's an obvious one - in half of all pregnancies, the sex of the child is male. The mother is female. I'm pretty sure you can't be both at once.
If you want to boil it down, the baby is a parasite. It is not your body. At no point in pregnancy is the developing embryo or fetus simply a part of the mother's body.
The baby might be in your body, but that doesn't mean it is your body. And it certainly doesn't give you the right to kill it.




I CAN'T TAKE CARE OF IT AND GIVE IT THE LIFE IT DESERVES.

Put it up for adoption. Better for it to have a life than to murder it.


YOU'RE NOT KILLING IT BECAUSE IT ISN'T ALIVE.

The most ignorant of them all, and the easiest to refute.
Simply put, it is alive. Quote from abort73.com:

Every new life begins at conception. This is an irrefutable fact of biology. It is true for animals and true for humans. When considered alongside the law of biogenesis – that every species reproduces after its own kind – we can draw only one conclusion in regard to abortion. No matter what the circumstances of conception, no matter how far along in the pregnancy, abortion always ends the life of an individual human being. Every honest abortion advocate concedes this simple fact.

Faye Wattleton, the longest reigning president of the largest abortion provider in the world – Planned Parenthood – argued as far back as 1997 that everyone already knows that abortion kills. She proclaims the following in an interview with Ms. Magazine:


"I think we have deluded ourselves into believing that people don't know that abortion is killing. So any pretense that abortion is not killing is a signal of our ambivalence, a signal that we cannot say yes, it kills a fetus."

Next.


THIS BABY WAS THE RESULT OF A RAPE OR SEXUAL ABUSE.

Better let abort73.com answer this:

You can't get very far in any discussion about abortion without considering the question of rape. Whereas the vast majority of pregnancies are the result of consensual sex, rape-based pregnancies present a unique dilemma. If a woman didn't choose to engage in sex in the first place, should she have to carry to term a child that was the result of her forced union? The question should become much clearer if we add in some hypothetical details. Let's say the woman does carry her child to term and decides to raise her son herself. After five years, however, she decides that the little boy's presence in her life is too much of a burden. He looks too much like his biological father. Should that mother have the right to kill her five year-old son who was born to her as a result of sexual assault?


Obviously not. No matter what the circumstances are regarding the little boy's conception, he is a human being with a right to life that cannot be taken away from him. But what about before the child is born, does this change anything? No, it doesn't. Abortion is an act of violence that kills a living human being. The circumstances surrounding the conception do not change this simple reality. Rape and abortion share this in common. They are both acts of violent assault against an innocent victim. Aborting a child conceived through rape simply extends this pattern of violence and victimhood. It does not "unrape" the woman, but it will almost certainly increase her regret and misery. Whereas rape is an act of violence for which she bears no responsibility, abortion is an act of violence for which she would be morally culpable.

This was regarding rape, but the whole set of "What if...?'s" can be found here: http://www.abort73.com/abortion/common_objections/


That's the major arguments I can think of at the moment. Here's what it boils down to:
No matter what the circumstances, no human has the right to take the life of another human.

Would it bother us more if they used guns?