Visitors inspect a Russian army S-400 Triumf mobile anti-aircraft missile system at a display of military vehicles during Russian Navy day at the Vistula lagoon in Baltiysk, Russia. (Photographer: Andrey Rudakov/Bloomberg)

Russia Rejected Iran S-400 Missile Request Amid Gulf Tension

(Bloomberg) -- Russia has rejected an Iranian request to buy S-400 missile defense systems, concerned that the sale would stoke more tension in the Middle East, according to two people with knowled...