Birth Control

So, I've been thinking about birth control, or rather the morality thererof.

It's an interesting topic. But let's get something straight out front. There's no question about birth control outside of marriage. It's wrong. Why? Because you shouldn't need it. Intercourse outside of the bounds of marriage is wrong--the Bible calls it fornication.

But what about the use of birth control inside of a committed marriage relationship? From what I can figure, there are two schools of thought.

The first is the conservative crowd. In their view, the products of intercourse are the potential for life. To do anything to prevent those products from creating life is to play God. For them, it is something akin to abortion--it's just as bad as aborting a new embryo. Advocates of this position would site the example of Onan in Genesis 38:8-10, who practiced the most basic form of birth control and was slain by the Lord as a result. However, it's important to note context. At that time in history, the people of Israel had been ordered to reproduce in order to create a mighty nation of the Lord's people. The problem with Onan's actions was that they were a violation of a command from the Lord more than a practice of birth control. That having been said, the previous points could still be valid.

Here's the other side--the somewhat more liberal (but still possible conservative) advocates of birth control. The idea is this: it is better to prevent it than to bring a child into the world who is unwanted. Unwanted children get neglected and abused. And then there's the situation where parents just simply can't afford any more children. In this case, then they become a burden on the welfare system...which then becomes a burden on everyone else. Both of these are moral issues.

Oh, but then there's another angle...the idea that birth control causes people to abdicate their responsibility, even married people.

I'm not sure what to think. What are your thoughts?