“Reliant Mermaid” is an annual joint naval and air force military training operation focusing on search and rescue operations held by Israel and the United States. Turkey used to take part in the operation as well but pulled out as of 2010 due to fraying diplomatic relations.
One of the main objectives for Israel in taking part was to strengthen its military relationship with Turkey and serve to dissuade hostile Arab countries from attacking Israel in the event of a broader Middle East war. Much of the Arab world, most notably Syria and Iran, denounced the annual operation, claiming that the United States is assisting in the organization of a new power axis in the Middle East.
The first iteration of the the training manuevers were conducted in international waters in the Mediterranena Sea in January 1998 involving the warships from all three countries. From 2000 until 2009, "Reliant Mermaid" was held every year to glowing reports from field commanders and military higher-ups. All the parties involved summarized the drills as a success and said it bettered military ties between the countries’ navies.
However, following the 2010 Gaza Flotilla incident, the drill was postponed with Turkey refusing to take part and was not reestablished until August 2012. That month, naval forces from the United States and Israel conducted the four day drill without the presence of Turkish forces for the first time in three years.
Besides testing seach and rescue abilities, the “Reliant Mermaid” drill also tested the U.S. Navy’s destroyer-mounted Aegis-missile defense system, which theoretically could defend Israel against Iranian nuclear missiles. The U.S. Navy, however, took pains to stress that the exercise bore no connection to the recent verbal escalation between Israel and Iran.
“Reliant Mermaid is a regularly scheduled exercise and is not associated with, or a reaction to any real world events,” a Navy Public Affairs Office spokesman said.
“This was a successful exercise which strengthened the bonds between the U.S. and Israeli navies and increased our ability to work together as a team,” said American Commanding Officer David A. Bretz.
"Reliant Mermaid 103" was held successfully in August 2013 and included a guided-missile destroyer from the U.S. 6th Fleet as well as missile boats from the Israeli Navy.
The Israeli Navy held joint drills with the U.S. and Greek Navies in May 2015. The training operation, named “Noble Dina,” began on April 27 with Israeli, Greek, and U.S. Navy commando, ships and submarines engaging in sea-air-land maneuvers.
Soldiers from Israel's Shayetet-13 Commando unit and U.S. Navy SEALs participated in a joint training operation in April 2017. The participants practiced parachuting into water combat situations, nighttime raids on ships, and various hostage rescue scenarios.
Sources: Ahronheim, Anna.Elite commandos from Israeli special ops team up with U.S. Navy SEALs,Jerusalem Post (April 7, 2017)
Lappin, Yaakov. “Israel holds naval drill with U.S., Greece,” Jerusalem Post (May 6, 2015)
Oren, Amir. “Israel, U.S. conduct joint naval exercises,” Haaretz (August 19, 2012)
Defense Video & Imagery Distribution System;
U.S. Navy. “Israel, Turkey, U.S. set to begin Reliant Mermaid exercise,”Defence Talk (August 17, 2009);
Israel Defense Forces