At what point will Ruth Kelly put principles first?

At the point when Ruth Kelly was forced to send her child to private school because New Labour was failing she should have resigned.

At the point when she lost an argument in Cabinet over gay adoption rights, she should have resigned.

More to the point isn't the fact that she opposes issues like gay adoption rights evidence that she simply is not suited to a Cabinet post with responsibility for diversity?

I don't expect change, New Labour doesn't understand principles.