Originally posted by the Voice of America. Voice of America content is produced by the Voice of America, a United States federal government-sponsored entity, and is in the public domain. Trump, Erdogan Discuss Turkey's Purchase of Russian Missile Defense System Steve Herman WHITE HOUSE - U.S. President Donald Trump on Wednesday welcomed Turkish President Recep Tayyip Erdogan to the White House for a second time at what is a low ebb in relations between Washington and Ankara. "We've been friends for a long time," Trump said in the Oval Office. "We understand each other's country." Erdogan recently infuriated U.S. officials when he ignored American warnings not to invade northeastern Syria in an operation targeting Syrian Kurds. The Turkish leader also upset American defense officials and diplomats with the purchase of the S-400 missile defense system from Moscow. The purchase violated the Countering America's Adversaries Through Sanction Act (CAATSA), which prohibits major purchases of Russian military hardware. That also prompted the United States to eject Turkey from its F-35 joint strike fighter program. .