Here is a screen-shot of the Vladivostok harbor:

As you can see it is a tri-corner area where China, Russia and South Korea come together. Both Russian and SK are at war with China. SK is fresh from its victory over North Korea.
Vladivostok is located on the small point at the top of the harbor. It contains a city/sea-pier with no visible ships and two air-fields. One airfield contains a landed Backfire bomber and a Shturm-S - whatever that is. The city contains one BTR-80 and one BMP-2.
A BMP-3 guards the town and power-station to the right of the harbor.
To the immediate left of the harbor is a parking lot full of soft Russian units - AA, light artillery, hand-held AT, bridging units, one or two MLRS.
At the top corner of the "parking lot" is a Russian naval fab with a sea-pier and air-field. This airfield has four or five old fighter planes, three Hoplite helos, a howitzer and an Airborne unit. There are no detectable ships.
The most dangerous Russian units on the harbor are the five submarines to the left of the Validvostok sea-pier. These prohibit any ship from approaching the city.
To the top left of the "parking lot" there is an active skirmish between SK tanks and Engineers and some Chinese APCs.
To the lower-left of the "parking lot" is another parking lot of SK units waiting to join the fray to the North.
I have been encouraging SK in this pursuit by donating tons of units to them, most of which they park around their Capital to the South. Whenever anyone makes me diplomatic trade offers for old units, I buy them and send them to SK. I did this for Mongolia too and it is now also surrounded with old units, but it is in no danger of being captured either.
The international center of the harbor is safe so I started running the P-3C Orion into there on patrol.
November 28th, 2020
A task group is sent North-West of the Shaklin Island airbase to attack and capture another Russian air-field there that threatens Shaklin. The TG has a single LPD full of amphib land units that will take the base. This operation goes off without a hitch. I left a garrison of three APCs and a DDG there and loaded the remaining units back onto the LPD. I moved all of my fighter planes from Japan to this newly captured air-field.
Sorties have been sent into Valadivostok harbor to try to figure out to take the city. Two DDG's attempts to destroy one of the BMPs with naval gunfire had very little effect. Unfortunitly these ships quickly discovered the submarines, which badly damaged one of the DDGs. It must await until the new sea-pier is completed to repair it.
Three U.S. submarines were also sent in, but they were out-numbered or out-classed by the five defending subs.
Fighter planes attempted to take out some of the Russian armor using air-to-ground missiles. That did not have much effect either. It was threfore decided to make more amphibious landings and eventually take Vladivostok by land.
December 4th, 2020
An LHD containing seven amphib and a supply vehicle attack the town of Nakhoda to the right of Vladivostok harbor. They immediately capture the town with only slight damage to an APC unit.
January 4th, 2021
An additional 15 APCs and Engineers land in Nakhoda.
January 9th, 2021
Thirty Marines are air-dropped 256 km North-East of Vladivostok, just East of another Russian airfield. These are soon joined by another 30 amphib land units.
Meanwhile one Seawolf submarine moves in on Vladivostok sea-pier and spots the Russian submarines. The Seawolf is destroyed on the mission. But this allows one F-35A multi-role fighter to attack the five deadly submarines using modded RUM-85A Sea Lance missiles to. All subs are destroyed in one sortie.
January 19th, 2021
Eight units from the newest landing proceed West inland and take the Russian air-field there. The U.S. now has 54 land units in mainland Russia at four different locations plus eight fighter aircraft.
February 1st, 2021
Two CVNs full of fighter jets move into Valadivostok harbor, protected by three submarines.
February 10th, 2021
15 amphib APCs move in and take Vladivostok with only minor casualties to themselves. This leaves it up to the Navy to "clean up" the 80 soft Russian units remaining in the "parking lot", so that the land units can safely claim the Rason Naval fab/sea-pier and the road for the U.S.
March 7th, 2021
Here is another screen-shot:

You can see that U.S. tanks have taken the last sea-pier/fab at Rason and the U.S. Navy is shooting up the last of the Russain hardware in the "parking lot" to the South-West.