Need help understanding this

My 1st move
-7 marines attack 2 tanks and 3 militia

His ? move
-2 tanks and mititia go to take madrid

NEW TURN

-madrid tanken
-marines did not attack and sat in enemies previous spot

This was all 1 cm away from madrid. Why did my marines not attack his units?

If I sent them to madrid would they attack or defend?

If you send them to Madrid they should defend


Your Marines didnt attack because his 1move attacks Madrid, then Your Marines walked totally chilled to the place where the Tanks where before, because when their Movement starts the Tanks cant be target anymore, perhaps the Tanks are lost in Battle, whatever, the Stack the Marines should attack isnet there anymore

Units in your own city are always defending, even if they came there by attacking an enemy.