Turkey straddles East and West. It's the buffer between Asia and Europe. And strategically, it's crucial. For the United States especially. But things are complicated.
The relationship between the U.S. and modern Turkey dates back nine decades.
After WWI, President Calvin Coolidge established diplomatic relations without congressional approval in February 1927.
Then, Turkey was one of the first UN countries to send troops during the Korean War, which made an impression. Turkey was soon welcomed into NATO in 1952.
The Cold War is a prime example. In exchange for economic help and protection the US got to establish military bases throughout Turkey getting within 150 miles of the USSR.
The Jupiter missiles US had in Turkey became a bargaining chip during the Cuban Missile Crisis. The Soviets agreed to dismantle their launch sites in Cuba if the Jupiter missiles would go, too.
More recently, Turkey's proximity to the Middle East has proven crucial.
On the other hand Turkey doesn't like the fact that the United States has trained Kurdish fighters in Iraq and Syria. The government argues they’re linked to separatist groups within Turkey.
A particular concern for the United States is Turkish president Recep Tayyip Erdogan. He pulled Turkey out of years of instability but he's consolidated power, and, in 2014, took authoritarian measures arresting protesters and journalists. Still the Obama administration, while officially condemning a July 2016 coup attempt, declared that the United States was, "steadfast in its support of Turkey’s democratically-elected government."
Turkey actually blames some Americans and Turks living in America for inciting the coup. After a dispute over punishment, the Trump administration rolled out tough sanctions, causing Turkey’s economy to falter.
So relations with Turkey are strained, to say the least. But they continue to be an important democratic partner in a section of the world at risk of extremism and iron-fisted rulers.