Psalm 135:10 He struck down great nations and slaughtered mighty kings--
Nations that loved God prospered...even if they turned their backs on God, when the loved God again and followed his commands God rebuilt their nation. God loves his people!! God wants to prosper His people! The only reason that God needs to destroy a nations that does not love Him, is to protect His people from harm. To protect His people from falling out from under the protection of Him because they get distracted by evil. Evils sometimes disguised in happy wrapping paper.
God loves his people...and He will even strike down great nations if that is what it takes to protect His people. God is for us when we love Him!! When we love God, He will send down is amazing grace upon our lives.