I’m really surprised the Russians had waited this long to make a move. Of course they have had that port of entry for a long time. It may turn out to be as simple as their interest in protecting their assets at the port and some other facilities. That at least could be viewed as a logical move that does not necessarily threaten anyone other then those that might want to destroy their property.
If the Marines leave the ship that would indicate something....otherwise ...not that big of a deal at present.