Security concerns dominated Soviet decisions concerning the Far East.
[52] Chief among these was gaining unrestricted access to the
Pacific Ocean. The year-round ice-free areas of the Soviet Pacific coastline—
Vladivostok in particular—could be blockaded by air and sea from
Sakhalin island and the
Kurile Islands. Acquiring these territories, thus guaranteeing free access to the
Soya Strait, was their primary objective.
[53][54] Secondary objectives were leases for the
Chinese Eastern Railway,
Southern Manchuria Railway,
Dairen, and
Port Arthur.
[55]