When King David took Bathesheba, did he not know that that was wrong?

You say:

 What’s your thought on David’s thinking when he decided he just had to have Bathsheba?

David obviously knew it was wrong to commit adultery with his Uriah’s wife, Psalm 51:1-3 shows this:

 To the choirmaster. A Psalm of David, when Nathan the prophet went to him, after he had gone in to Bathsheba. Have mercy on me, O God, according to your steadfast love; according to your abundant mercy blot out my transgressions.  (2)  Wash me thoroughly from my iniquity, and cleanse me from my sin!  (3)  For I know my transgressions, and my sin is ever before me.

Doubtless, David was tempted by carnal desire.  James 1:14-15 has a good description of how it works:

But each person is tempted when he is lured and enticed by his own desire.  (15)  Then desire when it has conceived gives birth to sin, and sin when it is fully grown brings forth death.