Yes, but Trump didn't start the birther controversy. I believe it was McCain and his cronies who started the thing. But Trump saw an opportunity and took it. I think Trump is right...I believe that Ted Cruz is qualified to be President, bit the democrats will have a field day with this if Cruz is the nominee.
1. Trump was not the catalyst for the story.
2. Trump saw a weakness, and helped the story run wild through "backhanded support" for Cruz.