The Pentagon will keep several thousand American troops in southeast Romania for at least nine more months, closer to the war in neighboring Ukraine than any other U.S. Army unit, officials said on Saturday. Over the last year, the sprawling Mihail Kogalniceanu Air Base, just a seven-minute rocket flight across the Black Sea from where Russian forces have settled in Crimea, has become a training hub for NATO forces in southeast Europe. The forces would be a first line of defense should Russia invade further west. There are around 4,000 U.S. soldiers with the 101st Airborne Division who have been...