According to Wikipedia: “The [U.S.] Marine Corps was founded to serve as an infantry unit aboard naval vessels and was responsible for the security of the ship and its crew by conducting offensive and defensive combat during boarding actions and defending the ship’s officers from mutiny…”
The U.S. Marine Corps is, in fact, part of the U.S. Navy and does not have a separate Secretariat as does the Army, Air Force and Navy, the Marine Corps being under the latter.
Some countries call them “Naval Infantry”. Originally ships fought each other with the goal being to board the enemy ship and capture it (BTW, the crew got bonuses based on what they captured, similar to pirates even though this was government work). Countries whose armed forces were created once boarding become unlikely, such as Israel, are unlikely to have a separate marine (navel infantry) unit.
For a more nuanced and Talmudic answer, consult Rav (Captain) Yitzchak Elson who recently retired as the Senior Chaplain of the Marine Corps after nearly 36 years of active duty. He held Shabbos services (albeit w/o Kiddush club) during operation Desert Storm and a full seder in newly liberated Baghdad…his email contacts are readily found via a google search….Rav Elson has semicha from YU and has published many meforshim, including perhaps one on the provenance of the term “Marines”