In 2004, "Essex" carried the 31st MEU to Kuwait, along with and . "Essex" stayed in the Persian Gulf while the 31st MEU and the combat element 1st Battalion, 3rd Marines went into Iraq for the Battle of Fallujah. During that time, "Essex" went to aid in Operation Unified Assistance in Banda Aceh, Indonesia after the December 2004 tsunami. She then returned to the Persian Gulf to embark the 31st MEU SOC and the combat element despite being in need of maintenance. After picking up the MEU and the Combat Element, the three ships returned to Okinawa, Japan. The ship had been at sea a total of eight months.