A close order formation is a military tactical formation in which soldiers are close together and regularly arranged for the tactical concentration of force. It was used by heavy infantry in ancient warfare, as the basis for shield wall and phalanx tactics, to multiply their effective weight of arms by their weight of numbers. In the Late Middle Ages, Swiss pikemen and German Landsknechts used close order formations that were similar to ancient phalanxes.
U.S President Donald Trump made a grand and dramatic arrival in Saudi Arabia, with six Royal Saudi Air Force F-15 fighter jets..