An Iranian soldier sitting atop a T-72 tank as it rolls past a portrait of Iran's supreme leader, Ali Khamenei during the Army Day parade in Tehran on April 18, 2015. Amid rising tension between Iran and Saudi Arabia, Iranian President Hassan Rouhani said that Iran's military is purely for defence and should not be seen as an aggressive threat in the Middle East. AFP PHOTO/BEHROUZ MEHRI (Photo credit should read BEHROUZ MEHRI/AFP/Getty Images)
