U.S. President Donald Trump has berated and belittled many of the European leaders expected to attend next week’s NATO summit in Turkey but has only praise for its host, Turkish President Recep Tayyip Erdogan. Erdogan has drawn on his close ties with the Republican president to secure Trump's presence at the Ankara event. Leveraging that friendship has helped Erdogan avoid the disarray that the U.S. president’s absence would cause the alliance. Trump has also hinted that he could make news during his visit related to jet engines and the potential sale of F-35 fighter jets barred for years because of Turkey’s closeness with Moscow.