Venezuelan President Nicolas Maduro is welcomed by Saudi Crown Prince Salman in Riyadh on Sunday. The meeting was part of Maduro's diplomatic tour of OPEC members to discuss falling oil prices, which have hit Venezuela's economy hard. Reuters /Landov hide caption

itoggle caption Reuters /Landov

Maj. Mariam Al Mansouri, the first Emirati female fighter pilot, flew in the first UAE airstrikes in the American-led campaign against ISIS. AP hide caption

itoggle caption AP

A Saudi woman poses in this picture to illustrate driving a car in Jiddah as part of a June 2011 protest. An advisory council recently recommended for the first time lifting a ban on female drivers. Susan Baaghil/Reuters/Landov hide caption

itoggle caption Susan Baaghil/Reuters/Landov

A member of the Saudi border guards mans a machine gun at the border with Iraq in July. Since the so-called Islamic State launched its offensive this summer in Iraq, Saudi Arabia has sent thousands of troops to the region. Faisal Nasser/Reuters/Landov hide caption

itoggle caption Faisal Nasser/Reuters/Landov

An A-18C Hornet attached to Strike Fighter Squadron (VFA) 87, prepares to launch from the flight deck of the aircraft carrier USS George H.W. Bush (CVN 77) to conduct strike missions against Islamic State group targets. Robert Burck/AP hide caption

itoggle caption Robert Burck/AP

A photo released by the U.S. Navy shows the guided-missile cruiser USS Philippine Sea launching a Tomahawk cruise missile against Islamic State targets in Syria on Tuesday. Eric Garst/U.S. Navy/EPA/Landov hide caption

itoggle caption Eric Garst/U.S. Navy/EPA/Landov

A photo provided by Lockheed Martin shows a test of its THAAD missile interceptor system. The Pentagon has awarded a contract worth more than $3.9 billion for the system. Lockheed Martin hide caption

itoggle caption Lockheed Martin

A family of elephants in Kenya's Maasai Mara game reserve. Tony Karumba/AFP/Getty Images hide caption

itoggle caption Tony Karumba/AFP/Getty Images