All the way up to the fall of the Iron Curtain, the Warsaw Pact planned on invading Denmark as part of a NATO vs Warsaw Pact war.
Seizing the straits and islands of Denmark would have had several benefits for the Pact:
- Prevent NATO reinforcements to land from Norway, UK and USA on their northern flank
- Clear the Baltic Sea from counter attack
- Use Danish airfields as operations bases to defend against attacks from the British Isles
- Open a southern flank against Norway
- Free movement in and out of the Baltic Sea and the Atlantic Ocean
- Destabilise NATO politically by defeating one of its members
Pact forces would have attacked through northern Germany to capture and hold the peninsula of Jutland. North of Hamburg, they would have faced a combined force of West Germans and Danes under Danish command - possibly supported by British and US forces, had they had time to arrive.
To seize the Danish islands and the capital of Copenhagen, the Polish army would have conducted the invasion. They would have landed paratroopers and conducted a beach landing in Fakse Bay on Zealand.
Defending the Danish isles would have been poorly equipped and trained Danish forces, some with equipment and weapons dating back to World War 2. However, on the sea their mine laying capabilities were good and they had a number of fast going warships that combined would have made a naval invasion tough for the invaders.
The Danes outnumber the invading force by far. They are backed by a large home guard fighting in their own local areas, in prepared ambush. However, they are poorly equipped compared to their Pact counterparts, especially concerning NBC warfare.
Furthermore, Pact forces would have had 1,450 tanks more than the defenders.
Would the Danes and the West Germans have had enough of a home ground advantage to stop the better equipped Pact armies from taking northern Germany and Denmark?