On the landings in Korea, it wasn't until October that Kim Il-Sung was returned to Korea and this was via landing at Wonsan; my understanding is that several brigades began to arrive at this time via the same method although I'm having trouble re-finding the source in question for it. As a general overview, I defer to Michael Sandusky's America's Parallel, which states that the situation in Mid-August was that there was only two Soviet divisions stalled out around Chongjin-still north of the 41st parallel-against around 9 Japanese divisions throughout Korea. Limited landings did occur at this time around the Eastern Korean coastline but these were extremely limited and damn near disastrous. Pyongyang was actually occupied by air lifted Soviet officers, not the arrival of serious Red Army forces.
The Soviet landing at Wonsan occurred on August 21, with overland forces linking up by August 25th. The bulk of the 25th Army is dated as arriving along the 38th Parallel at about the same time. American forces did not land in the south until early-September. Undoubtedly all of this was facilitated by the Japanese surrender and without that, the Soviets would have likely taken several more months to finish up dealing with Manchuria and Korea, but then the Americans would never have the opportunity to even set foot in Korea without the Japanese surrender.
As for the logistics thing, I think you've misunderstood what I was trying to say; there was no existing serious ports in the Kuriles to allow for a major landing against Hokkaido.
Well, the most likely launch point for such an invasion would probably be Vladivostok, not the Kuriles, so I don’t really see why that matters?
They had enough sea lift capacity to deposit one Rifle division at a time even without losing the LCIs. The Japanese had something like three, including elite formations, on Hokkaido in August of 1945.
The combined total of Soviet amphibious operations in mid-August amount to a corps of forces being landed simultaneously (one division in Korea, two at Shumshu, and a reinforced brigade on Sakhalin). There may also be a brigade-sized air drop by the VDV. Merchant marine As for the Japanese three divisions, you seem unable to grasp that three divisions is a very small force for the size of coastline Hokkaido presents so their presence on the island in general is less important then precisely where on the island they are when the Soviets land. In late-August, they were mostly deployed facing north and east, with the western coastline bare, but it’s possible the Japanese may simply redeploy them in the interim.
Also, looking into it, the invasions of North Korea did involve landing light armor, about a company of T-26s, so it shows the Soviets did have some minimal capacity to put armor ashore.
And yet, they didn't deploy these vessels to aid their landings in Korea nor the Kuriles. That's very telling.
Quite a number of them were deployed to the Kuriles: there were a total of 64 vessels of all types deployed as was. As for the rest, they were absorbed by the other operations. The Soviets were conducting simultaneous operations in North Korea (56 vessels initially, with further allotments following) and Sakhalin (32 vessels), as well as patrols in the Sea of Japan and preparations for a future Hokkaido operation.
So, in other words, nowhere near a port to allow them to deposit armor and nowhere near close enough an air base. The Japanese had 400 aircraft on Hokkaido in August of 1945...
I refer to you to my earlier point about how the Japanese had inadequate forces to garrison all the ports and hence the Soviets very much might have been able to find a undefended port to land at, possibly even with a nearby airfield. The nearest Japanese forces to the port town of Rumoi, for example, was a single coastal defense point, which maxes out at about battalion strength, 40 kilometers to the south. The operational status of the Japanese aircraft on Hokkaido is questionable, seeing as all available fuel was being allocated for the defense of Kyushu and Honshu, to say nothing of the questions surrounding the quality of the craft and pilots.
The Soviets had zero chance of carrying out a successful landing on Hokkaido in 1945. They would have been busy with Manchuria and Sakhalin and had basically no capacity to carry out anything near what the US or even the British (Operation Zipper) were doing in terms of amphibious warfare.
The obvious flaw in that assumption is that they would need what the US or British were doing in amphibious warfare. This isn't Iwo Jima or Normandy we're talking about here. Hell, as I observed earlier, it isn't even Shumshu.
Moderately related - the Soviet landing in the Kuriles (Shumshu and Paramushiro) was and would have been an unmitigated disaster. Had the war continued General Gnechko's tiny force would have been totally annihilated.
Yeah, that doesn't fit with what was happening on Shumshu at all. By the time the Japanese garrison laid down their arms, the Japanese shore batteries had already been destroyed and the Soviets had a solid, secure beachhead which was receiving a steady flow of reinforcements, including heavy artillery. The attempted counterattack by the 11th tank regiment the day before had seen it completely wiped out (the wreckage of it's tanks are still there too this day). That the force experienced difficulties in establishing the beachhead is well recorded, but at no point was it at risk in being wiped out.