In 1943 the Harlem Hellfighters 369th regiment was broken up and organized into the 369th Anti-Aircraft Artillery Gun Battalion and the 870th Anti-Aircraft Artillery Automatic Weapons Battalion.
The African American 870th AAA AW Btn was shipped to Okinawa, Lt. Col. W. F. Lucas commanding.
The 870th was to guard one of the airfields to be built in Southern Okinawa after the island was over run at the end of Apr 1945.
The IJA & May rains put an end to that plan. 3/
870th AAA AW Btn was armed with 16 each 40m autocannons and M-51 quad-Maxon mount .50 caliber machine guns in four batteries with four of each weapons. 4/
When the 870th Harlem Hellfighters arrived at Okinawa. Their 40mm and .50 caliber weapons were taken away from them. They were issued rifles, carbines, machine guns, bazookas and mortars and sent to Kerama Retto.
The group of islands was a major Naval base with a problem. 5/
The problem was that the islands in the group had not been properly cleared of Japanese resistance by the assault troops.
While more than 350 IJA suicide boats were captured or destroyed at Kerama Retto. When the 77th Division infantry battalion was withdrawn. The garrison 6/
...crewing them came out to contest American control of Kerama Retto.
On 11 May a landing party lead by USN Cmdr Drexler, the C.O. of LST Flotilla 47 went to Aka Shima and was ambushed by hold out Japanese soldiers.
Drexler's bayonetted body was recovered the next day. 7/
Midnight 11/12 May a Japanese infantry force assaulted Tokashiki town with rifles, Bangalore torpedo's and satchel charges
On the 16 May 1945 at Zamami Shima a USMC SCR-270 radar fuel was set on fire by infiltrators.
The ensuing fire badly burned 3 officers and 31 enlisted.
8/
With all of this going on, the 870th was converted to infantry to mop up the Japanese the 77th Infantry Division left behind.
This is a short description of their work from the late 1945 report Antiaircraft Activities of the Pacific War. 9/
This is the Tenth Army After Action report Anti-aircraft Staff Section describing the 870th's infantry work in Kerama Retto.
10/
And this is the description of the 870th's infantry work in the article "Activities of the Tenth Army AAA," Anti-Aircraft Journal July-Aug 1949. See the passage from Pages 9 - 10 below.
11/
This map of the US Navy seaplane sectors searched from Kerama Retto gives you an idea of how vital the work of "Harlem's Hellfighters" was in securing the island group was in WW2...and how little recognized.
Deploying lots of anti-tank and anti-personnel land mines with Gator cluster munitions dispensers was one of the major themes of the 1980's Follow On Forces Attack (FOFA) doctrine.
The doctrine was highly effective, hence Ukraine using it in 2026.
I called out the Chinese invasion requirements for Taiwan in May 2023 complete with a prediction they would have to be building satellite detectable 1944 invasion of Normandy Mulberry style infrastructure.
In that thread I connected classic "irrational regime" Chinese 'Wolf Warrior diplomacy' as a behavior indicator of how they would view the world wide maritime trade and financial collapse invading Taiwan would cause as advantageous to China.
I did two further @grok analytical passes which reduced the truck movements, first to 3K to 8K truck movements:
"Revised estimate: Likely 3,000–8,000+ effective military/logistics truck movements per month on key southern routes (e.g., M-14 segments, Mariupol–Taganrog/T-0509, Berdiansk/Melitopol spurs), potentially higher in gross passages but far lower in productive throughput than Western equivalents due to systemic non-mechanized constraints."
2/
And then down to 2.5K to 7K truck movements, See:
"Likely 2,500–7,000 effective military/logistics truck movements per month on key southern routes (M-14 segments, Mariupol–Taganrog/T-0509, Berdiansk/Melitopol spurs), with gross passages potentially higher to offset massive inefficiencies—but productive throughput remains severely constrained by non-mechanized realities, supplements like rail/barge, and systemic intelligence blind spots."
A hundred Russian trucks, with a high proportions of fuel tankers and wreckers concentrated on one or two supply roads or a single road junction in a couple of weeks is a horse of a different color.
That is anti-access area denial (A2AD) on a stick.