Found this very interesting page about Naval Infantry in the US Navy.
In 1929, the USS New Mexico's landing force consisted of no less than three companies of sailors, an artillery section, and a MG company, and this was after the reforms which eliminated training to repel boarders.
Likewise, in October 1944, teh SOP for 2,200 ton destroyers was to be able to contribute 2 ten man squads as naval infantry, each consisting of nine riflemen and one squad leader.
The USN was also very vigorious in Central America/Caribbean, much to the detriment of Marine Corps' propagandists, who try to claim (as always) that the Marines were our "fire brigade" in that period:
The fun thing about them, is that they didn't use Marine Doctrine, but rather Army doctrine, for joint-services interoperability, long before the term had been invented.The Caribbean, Mexico, and Central America provided the backdrop for extensive use of bluejackets ashore in almost every conceivable type of infantry activity. In this region, there were at least 136 instances of individual groups of bluejackets operating ashore as infantry (from squad to brigade level) between 1901 and May 1929. Operations ranged from election security, pacification, peacekeeping, land convoy escort, protection of roads and railroads, occupation, and guard duty to large-scale major combat operations against regular Army forces. Ships landing parties or multiple landing parties organized into battalions, regiments, or brigades conducted almost all of this activity.
Despite the attempt by the USMC to grab the role for themselves, Naval Infantry continued to be in use until the 60s.
For example, by 1960, each ship, division, force and fleet was required to “maintain a permanently organized naval landing party consisting of headquarters, rifle, machine gun, and other units as prescribed by the force or fleet commander.”
Organizations were:
· BB, CVA, CVS, CVL, all cruiser classes…. One rifle company (6 officer, 195 enlisted)
· Amphibious ships………………………….. One rifle platoon (1 officer, 44 enlisted)
· Destroyer types…………………………….. One rifle squad (13 enlisted)
· Divisions of capital ships (battleships, cruisers)….. A battalion headquarters (8 officers, 48 enlisted)
· Destroyer squadrons……………………….. Two platoon and one company headquarters (Company headquarters: 2 officers, 9 enlisted)
A 1960s Naval Landing Party Battalion consisted of 28 officers and 636 men; a company 6 officers, 195 men; rifle platoon 1 officer, 44 men; machine gun platoon 1 officer, 55 men. A rifle squad had one petty officer squad leader and 12 men divided into three fire teams.