I think again as I said in the other post is not God's unfairness or His harshness . It is the people who made those bad decisions and being a just God , He let them make those bad decisions.because ultimately they will have to pay for their wrongs.
You're right--it's not about God being unfair or harsh. But I see another difficulty here: These passages speak of God doing more than merely passively sitting back and allowing people to make bad decisions. They portray him as actively doing something in response to the bad decisions. So, you see, I'm not so sure that saying God "let them make those bad decisions" really does justice to the text.