In my mind, adoption is driven by the needs and desires of adults. Children do not make the decisions in adoption (or parenting for that matter), so there has to be an essential self-serving motivation by adults to make anything happen. That self-serving motivation may be the good feeling one gets from making a difference in someone's life.
That being said, those needs and desires of adults should not violate the needs and desires of children, nor should they stomp on the rights of other adults. So if there is a conflict of those needs and desires ... the kids win. No contest.
I agree totally with Riley6, you don't want people adopting children who aren't driven to do so. So just the fact that there are waiting children needing a family, does not mean that Donald Trump should adopt children just because he has the means to (sorry if I offended any Trump fans
)