President Donald Trump has berated and belittled many of the European leaders who are expected to attend the upcoming NATO summit in Turkey. But Trump has offered only praise for the summit host, Turkish President Recep Tayyip Erdogan. Erdogan has drawn on his close ties with the Republican president to secure Trump's presence at the summit. Leveraging that friendship has helped Erdogan avoid the disarray that Trump's absence of the summit might have caused. Trump has hinted he could make news during his visit related to jet engines and the potential sale of F-35 fighter jets. That's been barred for years because of Turkey’s closeness with Russia.