Is God Just?

I've been having a conversation with Gill, an atheist, and it has caused me to think about some things.  One question that I'm dealing with is, "is God just?".  Gill and many atheists would say no.  And of course, we are talking about the Christian God, the God of the Christian Bible.  I think reasons Gill would give for saying that God is not just is:

• all mankind is suffering for the sin of Adam and Eve
• many innocent children and unborn children were killed by God in the flood (during Noah's time)
• nations were wiped out, including innocent children, at the command of God
• God allowed slavery, the owning of people, even among those people God called his own (the Jewish people)

I think the Bible surely claims that God is just.  Is that true?  Here are some thoughts:

God doesn't claim to be fair.  Not everyone is treated the same.  God may show mercy on whom he shows mercy.  But that doesn't mean that God is not just.  To be unjust is to treat someone in a way they don't deserve.

For me, this comes down to children.  God does not punish innocent children, but sometimes their death is included in the punishment of their father.  An example is Korah's rebellion.

Another thought.  I think God's actions in the OT were meant to perserve his people, or even mankind as a whole.  What would have happened if men were able to do all that they set their minds to, as in the days of the Tower of Babylon?  But God interviened.  Perhaps a better view of the justice of God will be ours when we see the full picture, including what happens to people in the age to come.