"Once you grasp the geographical spread of Trump’s interests, it is hard to see how the potential conflicts of interest could ever be resolved."

"Take the Middle East, a region of the world that every modern American President has had to focus on. According to the Post, in addition to the Trump-branded real-estate development in Turkey, Trump has business ties to Qatar and the United Arab Emirates, two oil-rich countries that have funded radical Islamic movements. And, just last year, Trump registered eight companies named after Jeddah, the second-largest city in Saudi Arabia. It’s not just that Trump won’t be seen as an honest broker in the Middle East. He wouldn’t be seen as broker of any kind but as a principal and business partner of some of the region’s repressive governments and their cronies. Even if, for the duration of his Presidency, Trump were to put his businesses into a properly independent trust, run by business executives not connected to him, the Trump-owned and Trump-branded companies would still be generating income for the President and his family. He and his advisers would know that. The governments of the countries where the companies are located would know that. And so would the rest of us."

Writes John Cassidy.